diff --git a/DEPS b/DEPS
index ba077594fe4..68a34a5e988 100644
--- a/DEPS
+++ b/DEPS
@@ -107,7 +107,7 @@ vars = {
 
   "chromedriver_tag": "83.0.4103.39",
   "dartdoc_rev" : "305713608c25106d95f9114418d895e08d1a9e9c",
-  "devtools_rev" : "e138d55437a59838607415ef21f20bd6c4955dbc",
+  "devtools_rev" : "b3bf672474a2bff82f33e1176aa803539baa0d60+1",
   "jsshell_tag": "version:88.0",
   "ffi_rev": "f3346299c55669cc0db48afae85b8110088bf8da",
   "fixnum_rev": "16d3890c6dc82ca629659da1934e412292508bba",
diff --git a/pkg/vm_service/CHANGELOG.md b/pkg/vm_service/CHANGELOG.md
index 47f3893bdcb..1613626b9dd 100644
--- a/pkg/vm_service/CHANGELOG.md
+++ b/pkg/vm_service/CHANGELOG.md
@@ -1,4 +1,9 @@
 # Changelog
+
+## 7.1.0
+- Update to version `3.46` of the spec.
+- Move `sourcePosition` properties into `ClassRef`, `FieldRef`, and `FuncRef`.
+
 ## 7.0.0
 - *breaking bug fix*: Fixed issue where response parsing could fail for `Context`.
 - Add support for `setBreakpointState` RPC and updated `Breakpoint` class to include
diff --git a/pkg/vm_service/example/vm_service_assert.dart b/pkg/vm_service/example/vm_service_assert.dart
index c861f827c8e..f9f2d6e8bbd 100644
--- a/pkg/vm_service/example/vm_service_assert.dart
+++ b/pkg/vm_service/example/vm_service_assert.dart
@@ -317,6 +317,7 @@ vms.ClassRef assertClassRef(vms.ClassRef obj) {
   assertNotNull(obj);
   assertString(obj.id!);
   assertString(obj.name!);
+  assertLibraryRef(obj.library!);
   return obj;
 }
 
@@ -331,10 +332,10 @@ vms.Class assertClass(vms.Class obj) {
   assertNotNull(obj);
   assertString(obj.id!);
   assertString(obj.name!);
+  assertLibraryRef(obj.library!);
   assertBool(obj.isAbstract!);
   assertBool(obj.isConst!);
   assertBool(obj.traceAllocations!);
-  assertLibraryRef(obj.library!);
   assertListOfInstanceRef(obj.interfaces!);
   assertListOfFieldRef(obj.fields!);
   assertListOfFuncRef(obj.functions!);
diff --git a/pkg/vm_service/java/version.properties b/pkg/vm_service/java/version.properties
index d9345163f32..9e3fb907bc8 100644
--- a/pkg/vm_service/java/version.properties
+++ b/pkg/vm_service/java/version.properties
@@ -1 +1 @@
-version=3.45
+version=3.46
diff --git a/pkg/vm_service/lib/src/dart_io_extensions.dart b/pkg/vm_service/lib/src/dart_io_extensions.dart
index 73b3b842654..9e9faaf2b09 100644
--- a/pkg/vm_service/lib/src/dart_io_extensions.dart
+++ b/pkg/vm_service/lib/src/dart_io_extensions.dart
@@ -485,7 +485,7 @@ class HttpProfileRequestData {
   HttpProfileRequestData.buildErrorRequest({
     required this.error,
     required this.events,
-  })   : _connectionInfo = null,
+  })  : _connectionInfo = null,
         _contentLength = null,
         _cookies = [],
         _followRedirects = null,
diff --git a/pkg/vm_service/lib/src/vm_service.dart b/pkg/vm_service/lib/src/vm_service.dart
index a42219a453a..a460c69aed1 100644
--- a/pkg/vm_service/lib/src/vm_service.dart
+++ b/pkg/vm_service/lib/src/vm_service.dart
@@ -26,7 +26,7 @@ export 'snapshot_graph.dart'
         HeapSnapshotObjectNoData,
         HeapSnapshotObjectNullData;
 
-const String vmServiceVersion = '3.45.0';
+const String vmServiceVersion = '3.46.0';
 
 /// @optional
 const String optional = 'optional';
@@ -2690,8 +2690,8 @@ class AllocationProfile extends Response {
                 as List? ??
             []);
     memoryUsage =
-        createServiceObject(json['memoryUsage']!, const ['MemoryUsage'])
-            as MemoryUsage;
+        createServiceObject(json['memoryUsage'], const ['MemoryUsage'])
+            as MemoryUsage?;
     dateLastAccumulatorReset = json['dateLastAccumulatorReset'] is String
         ? int.parse(json['dateLastAccumulatorReset'])
         : json['dateLastAccumulatorReset'];
@@ -2743,9 +2743,9 @@ class BoundField {
   });
 
   BoundField._fromJson(Map<String, dynamic> json) {
-    decl = createServiceObject(json['decl']!, const ['FieldRef']) as FieldRef;
+    decl = createServiceObject(json['decl'], const ['FieldRef']) as FieldRef?;
     value =
-        createServiceObject(json['value']!, const ['InstanceRef', 'Sentinel'])
+        createServiceObject(json['value'], const ['InstanceRef', 'Sentinel'])
             as dynamic;
   }
 
@@ -2800,7 +2800,7 @@ class BoundVariable extends Response {
 
   BoundVariable._fromJson(Map<String, dynamic> json) : super._fromJson(json) {
     name = json['name'] ?? '';
-    value = createServiceObject(json['value']!,
+    value = createServiceObject(json['value'],
         const ['InstanceRef', 'TypeArgumentsRef', 'Sentinel']) as dynamic;
     declarationTokenPos = json['declarationTokenPos'] ?? -1;
     scopeStartTokenPos = json['scopeStartTokenPos'] ?? -1;
@@ -2875,7 +2875,7 @@ class Breakpoint extends Obj {
     enabled = json['enabled'] ?? false;
     resolved = json['resolved'] ?? false;
     isSyntheticAsyncContinuation = json['isSyntheticAsyncContinuation'];
-    location = createServiceObject(json['location']!,
+    location = createServiceObject(json['location'],
         const ['SourceLocation', 'UnresolvedSourceLocation']) as dynamic;
   }
 
@@ -2914,15 +2914,28 @@ class ClassRef extends ObjRef {
   /// The name of this class.
   String? name;
 
+  /// The location of this class in the source code.
+  @optional
+  SourceLocation? location;
+
+  /// The library which contains this class.
+  LibraryRef? library;
+
   ClassRef({
     required this.name,
+    required this.library,
     required String id,
+    this.location,
   }) : super(
           id: id,
         );
 
   ClassRef._fromJson(Map<String, dynamic> json) : super._fromJson(json) {
     name = json['name'] ?? '';
+    location = createServiceObject(json['location'], const ['SourceLocation'])
+        as SourceLocation?;
+    library = createServiceObject(json['library'], const ['LibraryRef'])
+        as LibraryRef?;
   }
 
   @override
@@ -2934,7 +2947,9 @@ class ClassRef extends ObjRef {
     json['type'] = type;
     json.addAll({
       'name': name,
+      'library': library?.toJson(),
     });
+    _setIfNotNull(json, 'location', location?.toJson());
     return json;
   }
 
@@ -2942,7 +2957,8 @@ class ClassRef extends ObjRef {
 
   operator ==(other) => other is ClassRef && id == other.id;
 
-  String toString() => '[ClassRef id: ${id}, name: ${name}]';
+  String toString() =>
+      '[ClassRef id: ${id}, name: ${name}, library: ${library}]';
 }
 
 /// A `Class` provides information about a Dart language class.
@@ -2953,6 +2969,13 @@ class Class extends Obj implements ClassRef {
   /// The name of this class.
   String? name;
 
+  /// The location of this class in the source code.
+  @optional
+  SourceLocation? location;
+
+  /// The library which contains this class.
+  LibraryRef? library;
+
   /// The error which occurred during class finalization, if it exists.
   @optional
   ErrorRef? error;
@@ -2966,13 +2989,6 @@ class Class extends Obj implements ClassRef {
   /// Are allocations of this class being traced?
   bool? traceAllocations;
 
-  /// The library which contains this class.
-  LibraryRef? library;
-
-  /// The location of this class in the source code.
-  @optional
-  SourceLocation? location;
-
   /// The superclass of this class, if any.
   @optional
   ClassRef? superClass;
@@ -3006,17 +3022,17 @@ class Class extends Obj implements ClassRef {
 
   Class({
     required this.name,
+    required this.library,
     required this.isAbstract,
     required this.isConst,
     required this.traceAllocations,
-    required this.library,
     required this.interfaces,
     required this.fields,
     required this.functions,
     required this.subclasses,
     required String id,
-    this.error,
     this.location,
+    this.error,
     this.superClass,
     this.superType,
     this.mixin,
@@ -3026,14 +3042,14 @@ class Class extends Obj implements ClassRef {
 
   Class._fromJson(Map<String, dynamic> json) : super._fromJson(json) {
     name = json['name'] ?? '';
+    location = createServiceObject(json['location'], const ['SourceLocation'])
+        as SourceLocation?;
+    library = createServiceObject(json['library'], const ['LibraryRef'])
+        as LibraryRef?;
     error = createServiceObject(json['error'], const ['ErrorRef']) as ErrorRef?;
     isAbstract = json['abstract'] ?? false;
     isConst = json['const'] ?? false;
     traceAllocations = json['traceAllocations'] ?? false;
-    library = createServiceObject(json['library']!, const ['LibraryRef'])
-        as LibraryRef;
-    location = createServiceObject(json['location'], const ['SourceLocation'])
-        as SourceLocation?;
     superClass =
         createServiceObject(json['super'], const ['ClassRef']) as ClassRef?;
     superType = createServiceObject(json['superType'], const ['InstanceRef'])
@@ -3063,17 +3079,17 @@ class Class extends Obj implements ClassRef {
     json['type'] = type;
     json.addAll({
       'name': name,
+      'library': library?.toJson(),
       'abstract': isAbstract,
       'const': isConst,
       'traceAllocations': traceAllocations,
-      'library': library?.toJson(),
       'interfaces': interfaces?.map((f) => f.toJson()).toList(),
       'fields': fields?.map((f) => f.toJson()).toList(),
       'functions': functions?.map((f) => f.toJson()).toList(),
       'subclasses': subclasses?.map((f) => f.toJson()).toList(),
     });
-    _setIfNotNull(json, 'error', error?.toJson());
     _setIfNotNull(json, 'location', location?.toJson());
+    _setIfNotNull(json, 'error', error?.toJson());
     _setIfNotNull(json, 'super', superClass?.toJson());
     _setIfNotNull(json, 'superType', superType?.toJson());
     _setIfNotNull(json, 'mixin', mixin?.toJson());
@@ -3118,7 +3134,7 @@ class ClassHeapStats extends Response {
 
   ClassHeapStats._fromJson(Map<String, dynamic> json) : super._fromJson(json) {
     classRef =
-        createServiceObject(json['class']!, const ['ClassRef']) as ClassRef;
+        createServiceObject(json['class'], const ['ClassRef']) as ClassRef?;
     accumulatedSize = json['accumulatedSize'] ?? -1;
     bytesCurrent = json['bytesCurrent'] ?? -1;
     instancesAccumulated = json['instancesAccumulated'] ?? -1;
@@ -3378,7 +3394,7 @@ class ContextElement {
 
   ContextElement._fromJson(Map<String, dynamic> json) {
     value =
-        createServiceObject(json['value']!, const ['InstanceRef', 'Sentinel'])
+        createServiceObject(json['value'], const ['InstanceRef', 'Sentinel'])
             as dynamic;
   }
 
@@ -4015,6 +4031,10 @@ class FieldRef extends ObjRef {
   /// Is this field static?
   bool? isStatic;
 
+  /// The location of this field in the source code.
+  @optional
+  SourceLocation? location;
+
   FieldRef({
     required this.name,
     required this.owner,
@@ -4023,19 +4043,22 @@ class FieldRef extends ObjRef {
     required this.isFinal,
     required this.isStatic,
     required String id,
+    this.location,
   }) : super(
           id: id,
         );
 
   FieldRef._fromJson(Map<String, dynamic> json) : super._fromJson(json) {
     name = json['name'] ?? '';
-    owner = createServiceObject(json['owner']!, const ['ObjRef']) as ObjRef;
+    owner = createServiceObject(json['owner'], const ['ObjRef']) as ObjRef?;
     declaredType =
-        createServiceObject(json['declaredType']!, const ['InstanceRef'])
-            as InstanceRef;
+        createServiceObject(json['declaredType'], const ['InstanceRef'])
+            as InstanceRef?;
     isConst = json['const'] ?? false;
     isFinal = json['final'] ?? false;
     isStatic = json['static'] ?? false;
+    location = createServiceObject(json['location'], const ['SourceLocation'])
+        as SourceLocation?;
   }
 
   @override
@@ -4053,6 +4076,7 @@ class FieldRef extends ObjRef {
       'final': isFinal,
       'static': isStatic,
     });
+    _setIfNotNull(json, 'location', location?.toJson());
     return json;
   }
 
@@ -4091,6 +4115,10 @@ class Field extends Obj implements FieldRef {
   /// Is this field static?
   bool? isStatic;
 
+  /// The location of this field in the source code.
+  @optional
+  SourceLocation? location;
+
   /// The value of this field, if the field is static. If uninitialized, this
   /// will take the value of an uninitialized Sentinel.
   ///
@@ -4098,10 +4126,6 @@ class Field extends Obj implements FieldRef {
   @optional
   dynamic staticValue;
 
-  /// The location of this field in the source code.
-  @optional
-  SourceLocation? location;
-
   Field({
     required this.name,
     required this.owner,
@@ -4110,25 +4134,25 @@ class Field extends Obj implements FieldRef {
     required this.isFinal,
     required this.isStatic,
     required String id,
-    this.staticValue,
     this.location,
+    this.staticValue,
   }) : super(
           id: id,
         );
 
   Field._fromJson(Map<String, dynamic> json) : super._fromJson(json) {
     name = json['name'] ?? '';
-    owner = createServiceObject(json['owner']!, const ['ObjRef']) as ObjRef;
+    owner = createServiceObject(json['owner'], const ['ObjRef']) as ObjRef?;
     declaredType =
-        createServiceObject(json['declaredType']!, const ['InstanceRef'])
-            as InstanceRef;
+        createServiceObject(json['declaredType'], const ['InstanceRef'])
+            as InstanceRef?;
     isConst = json['const'] ?? false;
     isFinal = json['final'] ?? false;
     isStatic = json['static'] ?? false;
-    staticValue = createServiceObject(
-        json['staticValue'], const ['InstanceRef', 'Sentinel']) as dynamic;
     location = createServiceObject(json['location'], const ['SourceLocation'])
         as SourceLocation?;
+    staticValue = createServiceObject(
+        json['staticValue'], const ['InstanceRef', 'Sentinel']) as dynamic;
   }
 
   @override
@@ -4146,8 +4170,8 @@ class Field extends Obj implements FieldRef {
       'final': isFinal,
       'static': isStatic,
     });
-    _setIfNotNull(json, 'staticValue', staticValue?.toJson());
     _setIfNotNull(json, 'location', location?.toJson());
+    _setIfNotNull(json, 'staticValue', staticValue?.toJson());
     return json;
   }
 
@@ -4328,12 +4352,17 @@ class FuncRef extends ObjRef {
   /// Is this function const?
   bool? isConst;
 
+  /// The location of this function in the source code.
+  @optional
+  SourceLocation? location;
+
   FuncRef({
     required this.name,
     required this.owner,
     required this.isStatic,
     required this.isConst,
     required String id,
+    this.location,
   }) : super(
           id: id,
         );
@@ -4341,9 +4370,11 @@ class FuncRef extends ObjRef {
   FuncRef._fromJson(Map<String, dynamic> json) : super._fromJson(json) {
     name = json['name'] ?? '';
     owner = createServiceObject(
-        json['owner']!, const ['LibraryRef', 'ClassRef', 'FuncRef']) as dynamic;
+        json['owner'], const ['LibraryRef', 'ClassRef', 'FuncRef']) as dynamic;
     isStatic = json['static'] ?? false;
     isConst = json['const'] ?? false;
+    location = createServiceObject(json['location'], const ['SourceLocation'])
+        as SourceLocation?;
   }
 
   @override
@@ -4359,6 +4390,7 @@ class FuncRef extends ObjRef {
       'static': isStatic,
       'const': isConst,
     });
+    _setIfNotNull(json, 'location', location?.toJson());
     return json;
   }
 
@@ -4413,7 +4445,7 @@ class Func extends Obj implements FuncRef {
   Func._fromJson(Map<String, dynamic> json) : super._fromJson(json) {
     name = json['name'] ?? '';
     owner = createServiceObject(
-        json['owner']!, const ['LibraryRef', 'ClassRef', 'FuncRef']) as dynamic;
+        json['owner'], const ['LibraryRef', 'ClassRef', 'FuncRef']) as dynamic;
     isStatic = json['static'] ?? false;
     isConst = json['const'] ?? false;
     location = createServiceObject(json['location'], const ['SourceLocation'])
@@ -4600,7 +4632,7 @@ class InstanceRef extends ObjRef {
     kind = json['kind'] ?? '';
     identityHashCode = json['identityHashCode'] ?? -1;
     classRef =
-        createServiceObject(json['class']!, const ['ClassRef']) as ClassRef;
+        createServiceObject(json['class'], const ['ClassRef']) as ClassRef?;
     valueAsString = json['valueAsString'];
     valueAsStringIsTruncated = json['valueAsStringIsTruncated'];
     length = json['length'];
@@ -4984,7 +5016,7 @@ class Instance extends Obj implements InstanceRef {
     kind = json['kind'] ?? '';
     identityHashCode = json['identityHashCode'] ?? -1;
     classRef =
-        createServiceObject(json['class']!, const ['ClassRef']) as ClassRef;
+        createServiceObject(json['class'], const ['ClassRef']) as ClassRef?;
     valueAsString = json['valueAsString'];
     valueAsStringIsTruncated = json['valueAsStringIsTruncated'];
     length = json['length'];
@@ -5250,7 +5282,7 @@ class Isolate extends Response implements IsolateRef {
     livePorts = json['livePorts'] ?? -1;
     pauseOnExit = json['pauseOnExit'] ?? false;
     pauseEvent =
-        createServiceObject(json['pauseEvent']!, const ['Event']) as Event;
+        createServiceObject(json['pauseEvent'], const ['Event']) as Event?;
     rootLib = createServiceObject(json['rootLib'], const ['LibraryRef'])
         as LibraryRef?;
     libraries = List<LibraryRef>.from(
@@ -5519,7 +5551,7 @@ class InboundReference {
   });
 
   InboundReference._fromJson(Map<String, dynamic> json) {
-    source = createServiceObject(json['source']!, const ['ObjRef']) as ObjRef;
+    source = createServiceObject(json['source'], const ['ObjRef']) as ObjRef?;
     parentListIndex = json['parentListIndex'];
     parentField = createServiceObject(json['parentField'], const ['FieldRef'])
         as FieldRef?;
@@ -5744,8 +5776,8 @@ class LibraryDependency {
     isImport = json['isImport'] ?? false;
     isDeferred = json['isDeferred'] ?? false;
     prefix = json['prefix'] ?? '';
-    target = createServiceObject(json['target']!, const ['LibraryRef'])
-        as LibraryRef;
+    target = createServiceObject(json['target'], const ['LibraryRef'])
+        as LibraryRef?;
   }
 
   Map<String, dynamic> toJson() {
@@ -5807,19 +5839,19 @@ class LogRecord extends Response {
   });
 
   LogRecord._fromJson(Map<String, dynamic> json) : super._fromJson(json) {
-    message = createServiceObject(json['message']!, const ['InstanceRef'])
-        as InstanceRef;
+    message = createServiceObject(json['message'], const ['InstanceRef'])
+        as InstanceRef?;
     time = json['time'] ?? -1;
     level = json['level'] ?? -1;
     sequenceNumber = json['sequenceNumber'] ?? -1;
-    loggerName = createServiceObject(json['loggerName']!, const ['InstanceRef'])
-        as InstanceRef;
-    zone = createServiceObject(json['zone']!, const ['InstanceRef'])
-        as InstanceRef;
-    error = createServiceObject(json['error']!, const ['InstanceRef'])
-        as InstanceRef;
-    stackTrace = createServiceObject(json['stackTrace']!, const ['InstanceRef'])
-        as InstanceRef;
+    loggerName = createServiceObject(json['loggerName'], const ['InstanceRef'])
+        as InstanceRef?;
+    zone = createServiceObject(json['zone'], const ['InstanceRef'])
+        as InstanceRef?;
+    error = createServiceObject(json['error'], const ['InstanceRef'])
+        as InstanceRef?;
+    stackTrace = createServiceObject(json['stackTrace'], const ['InstanceRef'])
+        as InstanceRef?;
   }
 
   @override
@@ -5861,10 +5893,10 @@ class MapAssociation {
   });
 
   MapAssociation._fromJson(Map<String, dynamic> json) {
-    key = createServiceObject(json['key']!, const ['InstanceRef', 'Sentinel'])
+    key = createServiceObject(json['key'], const ['InstanceRef', 'Sentinel'])
         as dynamic;
     value =
-        createServiceObject(json['value']!, const ['InstanceRef', 'Sentinel'])
+        createServiceObject(json['value'], const ['InstanceRef', 'Sentinel'])
             as dynamic;
   }
 
@@ -6051,6 +6083,11 @@ class NullValRef extends InstanceRef {
           kind: InstanceKind.kNull,
           classRef: ClassRef(
             id: 'class/null',
+            library: LibraryRef(
+              id: '',
+              name: 'dart:core',
+              uri: 'dart:core',
+            ),
             name: 'Null',
           ),
         );
@@ -6098,6 +6135,11 @@ class NullVal extends Instance implements NullValRef {
           kind: InstanceKind.kNull,
           classRef: ClassRef(
             id: 'class/null',
+            library: LibraryRef(
+              id: '',
+              name: 'dart:core',
+              uri: 'dart:core',
+            ),
             name: 'Null',
           ),
         );
@@ -6323,7 +6365,7 @@ class ProfileFunction {
     exclusiveTicks = json['exclusiveTicks'] ?? -1;
     resolvedUrl = json['resolvedUrl'] ?? '';
     function =
-        createServiceObject(json['function']!, const ['dynamic']) as dynamic;
+        createServiceObject(json['function'], const ['dynamic']) as dynamic;
   }
 
   Map<String, dynamic> toJson() {
@@ -6433,8 +6475,8 @@ class ProcessMemoryUsage extends Response {
 
   ProcessMemoryUsage._fromJson(Map<String, dynamic> json)
       : super._fromJson(json) {
-    root = createServiceObject(json['root']!, const ['ProcessMemoryItem'])
-        as ProcessMemoryItem;
+    root = createServiceObject(json['root'], const ['ProcessMemoryItem'])
+        as ProcessMemoryItem?;
   }
 
   @override
@@ -6562,7 +6604,7 @@ class RetainingObject {
   });
 
   RetainingObject._fromJson(Map<String, dynamic> json) {
-    value = createServiceObject(json['value']!, const ['ObjRef']) as ObjRef;
+    value = createServiceObject(json['value'], const ['ObjRef']) as ObjRef?;
     parentListIndex = json['parentListIndex'];
     parentMapKey =
         createServiceObject(json['parentMapKey'], const ['ObjRef']) as ObjRef?;
@@ -6810,8 +6852,8 @@ class Script extends Obj implements ScriptRef {
 
   Script._fromJson(Map<String, dynamic> json) : super._fromJson(json) {
     uri = json['uri'] ?? '';
-    library = createServiceObject(json['library']!, const ['LibraryRef'])
-        as LibraryRef;
+    library = createServiceObject(json['library'], const ['LibraryRef'])
+        as LibraryRef?;
     lineOffset = json['lineOffset'];
     columnOffset = json['columnOffset'];
     source = json['source'];
@@ -6932,7 +6974,7 @@ class SourceLocation extends Response {
 
   SourceLocation._fromJson(Map<String, dynamic> json) : super._fromJson(json) {
     script =
-        createServiceObject(json['script']!, const ['ScriptRef']) as ScriptRef;
+        createServiceObject(json['script'], const ['ScriptRef']) as ScriptRef?;
     tokenPos = json['tokenPos'] ?? -1;
     endTokenPos = json['endTokenPos'];
   }
@@ -7235,7 +7277,7 @@ class Timeline extends Response {
   static Timeline? parse(Map<String, dynamic>? json) =>
       json == null ? null : Timeline._fromJson(json);
 
-  /// A list of timeline events. No order is guarenteed for these events; in
+  /// A list of timeline events. No order is guaranteed for these events; in
   /// particular, these events may be unordered with respect to their
   /// timestamps.
   List<TimelineEvent>? traceEvents;
diff --git a/pkg/vm_service/pubspec.yaml b/pkg/vm_service/pubspec.yaml
index a7db2e82b0e..9ea0b773b00 100644
--- a/pkg/vm_service/pubspec.yaml
+++ b/pkg/vm_service/pubspec.yaml
@@ -3,7 +3,7 @@ description: >-
   A library to communicate with a service implementing the Dart VM
   service protocol.
 
-version: 7.0.0
+version: 7.1.0
 
 homepage: https://github.com/dart-lang/sdk/tree/master/pkg/vm_service
 
diff --git a/pkg/vm_service/tool/dart/generate_dart.dart b/pkg/vm_service/tool/dart/generate_dart.dart
index 5e348b1e2fe..0f9897fd831 100644
--- a/pkg/vm_service/tool/dart/generate_dart.dart
+++ b/pkg/vm_service/tool/dart/generate_dart.dart
@@ -1491,6 +1491,8 @@ class Type extends Member {
       gen.writeln('identityHashCode: 0,');
       gen.writeln('kind: InstanceKind.kNull,');
       gen.writeln("classRef: ClassRef(id: 'class/null',");
+      gen.writeln("library: LibraryRef(id: '', name: 'dart:core',");
+      gen.writeln("uri: 'dart:core',),");
       gen.writeln("name: 'Null',),");
       gen.writeln(')');
     }
@@ -1640,10 +1642,9 @@ class Type extends Member {
         }
       } else {
         String typesList = _typeRefListToString(field.type.types);
-        String nullable =
-            field.optional && field.type.name != 'dynamic' ? '?' : '';
+        String nullable = field.type.name != 'dynamic' ? '?' : '';
         gen.writeln("${field.generatableName} = "
-            "createServiceObject(json['${field.name}']${field.optional ? '' : '!'}, "
+            "createServiceObject(json['${field.name}'], "
             "$typesList) as ${field.type.name}$nullable;");
       }
     });
diff --git a/runtime/observatory/lib/src/service/object.dart b/runtime/observatory/lib/src/service/object.dart
index 4db752a33b1..f3a26e775e7 100644
--- a/runtime/observatory/lib/src/service/object.dart
+++ b/runtime/observatory/lib/src/service/object.dart
@@ -4755,8 +4755,8 @@ void _upgradeCollection(collection, ServiceObjectOwner? owner) {
 
 void _upgradeMap(Map map, ServiceObjectOwner? owner) {
   map.forEach((k, v) {
-    if ((v is Map) && _isServiceMap(v)) {
-      map[k] = owner!.getFromMap(v);
+    if ((v is Map) && owner != null && _isServiceMap(v)) {
+      map[k] = owner.getFromMap(v);
     } else if (v is List) {
       _upgradeList(v, owner);
     } else if (v is Map) {
diff --git a/runtime/observatory/tests/service/get_version_rpc_test.dart b/runtime/observatory/tests/service/get_version_rpc_test.dart
index 1fe66c56493..5ff857b8608 100644
--- a/runtime/observatory/tests/service/get_version_rpc_test.dart
+++ b/runtime/observatory/tests/service/get_version_rpc_test.dart
@@ -12,7 +12,7 @@ var tests = <VMTest>[
     final result = await vm.invokeRpcNoUpgrade('getVersion', {});
     expect(result['type'], 'Version');
     expect(result['major'], 3);
-    expect(result['minor'], 45);
+    expect(result['minor'], 46);
     expect(result['_privateMajor'], 0);
     expect(result['_privateMinor'], 0);
   },
diff --git a/runtime/observatory_2/lib/src/service/object.dart b/runtime/observatory_2/lib/src/service/object.dart
index e2acf8a5e80..2baf6d5102f 100644
--- a/runtime/observatory_2/lib/src/service/object.dart
+++ b/runtime/observatory_2/lib/src/service/object.dart
@@ -4765,7 +4765,7 @@ void _upgradeCollection(collection, ServiceObjectOwner owner) {
 
 void _upgradeMap(Map map, ServiceObjectOwner owner) {
   map.forEach((k, v) {
-    if ((v is Map) && _isServiceMap(v)) {
+    if ((v is Map) && owner != null && _isServiceMap(v)) {
       map[k] = owner.getFromMap(v);
     } else if (v is List) {
       _upgradeList(v, owner);
diff --git a/runtime/observatory_2/tests/service_2/get_version_rpc_test.dart b/runtime/observatory_2/tests/service_2/get_version_rpc_test.dart
index bd9d9b13ead..809085615da 100644
--- a/runtime/observatory_2/tests/service_2/get_version_rpc_test.dart
+++ b/runtime/observatory_2/tests/service_2/get_version_rpc_test.dart
@@ -12,7 +12,7 @@ var tests = <VMTest>[
     var result = await vm.invokeRpcNoUpgrade('getVersion', {});
     expect(result['type'], equals('Version'));
     expect(result['major'], equals(3));
-    expect(result['minor'], equals(45));
+    expect(result['minor'], equals(46));
     expect(result['_privateMajor'], equals(0));
     expect(result['_privateMinor'], equals(0));
   },
diff --git a/runtime/vm/json_test.cc b/runtime/vm/json_test.cc
index db2e2f36db2..60c679e0099 100644
--- a/runtime/vm/json_test.cc
+++ b/runtime/vm/json_test.cc
@@ -171,23 +171,24 @@ ISOLATE_UNIT_TEST_CASE(JSON_JSONStream_DartObject) {
   }
   char buffer[1024];
   ElideJSONSubstring("classes", js.ToCString(), buffer);
+  ElideJSONSubstring("libraries", buffer, buffer);
+  ElideJSONSubstring("objects", buffer, buffer);
   EXPECT_STREQ(
-      "[{\"type\":\"@Instance\","
-      "\"_vmType\":\"null\","
-      "\"class\":{\"type\":\"@Class\",\"fixedId\":true,\"id\":\"\","
-      "\"name\":\"Null\"},"
-      "\"kind\":\"Null\","
-      "\"fixedId\":true,"
-      "\"id\":\"objects\\/null\","
-      "\"valueAsString\":\"null\"},"
-      "{\"object_key\":"
-      "{\"type\":\"@Instance\","
-      "\"_vmType\":\"null\","
-      "\"class\":{\"type\":\"@Class\",\"fixedId\":true,\"id\":\"\","
-      "\"name\":\"Null\"},"
-      "\"kind\":\"Null\","
-      "\"fixedId\":true,"
-      "\"id\":\"objects\\/null\","
+      "[{\"type\":\"@Instance\",\"_vmType\":\"null\",\"class\":{\"type\":\"@"
+      "Class\",\"fixedId\":true,\"id\":\"\",\"name\":\"Null\",\"location\":{"
+      "\"type\":\"SourceLocation\",\"script\":{\"type\":\"@Script\","
+      "\"fixedId\":true,\"id\":\"\",\"uri\":\"dart:core\\/null.dart\",\"_"
+      "kind\":\"kernel\"},\"tokenPos\":925,\"endTokenPos\":1165},\"library\":{"
+      "\"type\":\"@Library\",\"fixedId\":true,\"id\":\"\",\"name\":\"dart."
+      "core\",\"uri\":\"dart:core\"}},\"kind\":\"Null\",\"fixedId\":true,"
+      "\"id\":\"\",\"valueAsString\":\"null\"},{\"object_key\":{\"type\":\"@"
+      "Instance\",\"_vmType\":\"null\",\"class\":{\"type\":\"@Class\","
+      "\"fixedId\":true,\"id\":\"\",\"name\":\"Null\",\"location\":{\"type\":"
+      "\"SourceLocation\",\"script\":{\"type\":\"@Script\",\"fixedId\":true,"
+      "\"id\":\"\",\"uri\":\"dart:core\\/null.dart\",\"_kind\":\"kernel\"},"
+      "\"tokenPos\":925,\"endTokenPos\":1165},\"library\":{\"type\":\"@"
+      "Library\",\"fixedId\":true,\"id\":\"\",\"name\":\"dart.core\",\"uri\":"
+      "\"dart:core\"}},\"kind\":\"Null\",\"fixedId\":true,\"id\":\"\","
       "\"valueAsString\":\"null\"}}]",
       buffer);
 }
diff --git a/runtime/vm/object_service.cc b/runtime/vm/object_service.cc
index cc858f565fd..1c23fa8e76a 100644
--- a/runtime/vm/object_service.cc
+++ b/runtime/vm/object_service.cc
@@ -87,6 +87,13 @@ void Class::PrintJSONImpl(JSONStream* stream, bool ref) const {
   const String& scrubbed_name = String::Handle(ScrubbedName());
   const String& vm_name = String::Handle(Name());
   AddNameProperties(&jsobj, scrubbed_name.ToCString(), vm_name.ToCString());
+  const Script& script = Script::Handle(this->script());
+  if (!script.IsNull()) {
+    jsobj.AddLocation(script, token_pos(), end_token_pos());
+  }
+
+  jsobj.AddProperty("library", Object::Handle(library()));
+
   if (ref) {
     return;
   }
@@ -116,11 +123,6 @@ void Class::PrintJSONImpl(JSONStream* stream, bool ref) const {
     mix ^= interface_array.At(interface_array.Length() - 1);
     jsobj.AddProperty("mixin", mix);
   }
-  jsobj.AddProperty("library", Object::Handle(library()));
-  const Script& script = Script::Handle(this->script());
-  if (!script.IsNull()) {
-    jsobj.AddLocation(script, token_pos(), end_token_pos());
-  }
   {
     JSONArray interfaces_array(&jsobj, "interfaces");
     Type& interface_type = Type::Handle();
@@ -317,6 +319,12 @@ void Function::PrintJSONImpl(JSONStream* stream, bool ref) const {
   jsobj.AddProperty("const", is_const());
   jsobj.AddProperty("_intrinsic", is_intrinsic());
   jsobj.AddProperty("_native", is_native());
+
+  const Script& script = Script::Handle(this->script());
+  if (!script.IsNull()) {
+    jsobj.AddLocation(script, token_pos(), end_token_pos());
+  }
+
   if (ref) {
     return;
   }
@@ -348,11 +356,6 @@ void Function::PrintJSONImpl(JSONStream* stream, bool ref) const {
       jsobj.AddProperty("_field", field);
     }
   }
-
-  const Script& script = Script::Handle(this->script());
-  if (!script.IsNull()) {
-    jsobj.AddLocation(script, token_pos(), end_token_pos());
-  }
 }
 
 void FfiTrampolineData::PrintJSONImpl(JSONStream* stream, bool ref) const {
@@ -390,6 +393,12 @@ void Field::PrintJSONImpl(JSONStream* stream, bool ref) const {
   jsobj.AddProperty("static", is_static());
   jsobj.AddProperty("final", is_final());
   jsobj.AddProperty("const", is_const());
+
+  const class Script& script = Script::Handle(Script());
+  if (!script.IsNull()) {
+    jsobj.AddLocation(script, token_pos(), end_token_pos());
+  }
+
   if (ref) {
     return;
   }
@@ -416,10 +425,6 @@ void Field::PrintJSONImpl(JSONStream* stream, bool ref) const {
   } else {
     jsobj.AddPropertyF("_guardLength", "%" Pd, guarded_list_length());
   }
-  const class Script& script = Script::Handle(Script());
-  if (!script.IsNull()) {
-    jsobj.AddLocation(script, token_pos());
-  }
 }
 
 // See also Dart_ScriptGetTokenInfo.
diff --git a/runtime/vm/object_test.cc b/runtime/vm/object_test.cc
index 4d2a1fc97f5..6136da2b6bf 100644
--- a/runtime/vm/object_test.cc
+++ b/runtime/vm/object_test.cc
@@ -4344,8 +4344,16 @@ ISOLATE_UNIT_TEST_CASE(PrintJSONPrimitives) {
     Class& cls = Class::Handle(isolate->group()->object_store()->bool_class());
     cls.PrintJSON(&js, true);
     ElideJSONSubstring("classes", js.ToCString(), buffer);
+    ElideJSONSubstring("libraries", buffer, buffer);
+
     EXPECT_STREQ(
-        "{\"type\":\"@Class\",\"fixedId\":true,\"id\":\"\",\"name\":\"bool\"}",
+        "{\"type\":\"@Class\",\"fixedId\":true,\"id\":\"\",\"name\":\"bool\","
+        "\"location\":{\"type\":\"SourceLocation\",\"script\":{\"type\":\"@"
+        "Script\","
+        "\"fixedId\":true,\"id\":\"\",\"uri\":\"dart:core\\/bool.dart\","
+        "\"_kind\":\"kernel\"},\"tokenPos\":436,\"endTokenPos\":4432},"
+        "\"library\":{\"type\":\"@Library\",\"fixedId\":true,\"id\":\"\","
+        "\"name\":\"dart.core\",\"uri\":\"dart:core\"}}",
         buffer);
   }
   // Function reference
@@ -4359,14 +4367,23 @@ ISOLATE_UNIT_TEST_CASE(PrintJSONPrimitives) {
     ASSERT(!func.IsNull());
     func.PrintJSON(&js, true);
     ElideJSONSubstring("classes", js.ToCString(), buffer);
+    ElideJSONSubstring("libraries", buffer, buffer);
     EXPECT_STREQ(
-        "{\"type\":\"@Function\",\"fixedId\":true,"
-        "\"id\":\"\",\"name\":\"toString\","
-        "\"owner\":{\"type\":\"@Class\",\"fixedId\":true,\"id\":\"\","
-        "\"name\":\"bool\"},"
-        "\"_kind\":\"RegularFunction\","
-        "\"static\":false,\"const\":false,"
-        "\"_intrinsic\":false,\"_native\":false}",
+        "{\"type\":\"@Function\",\"fixedId\":true,\"id\":\"\","
+        "\"name\":\"toString\",\"owner\":{\"type\":\"@Class\","
+        "\"fixedId\":true,\"id\":\"\",\"name\":\"bool\","
+        "\"location\":{\"type\":\"SourceLocation\","
+        "\"script\":{\"type\":\"@Script\",\"fixedId\":true,"
+        "\"id\":\"\",\"uri\":\"dart:core\\/bool.dart\","
+        "\"_kind\":\"kernel\"},\"tokenPos\":436,\"endTokenPos\":4432},"
+        "\"library\":{\"type\":\"@Library\",\"fixedId\":true,\"id\":\"\","
+        "\"name\":\"dart.core\",\"uri\":\"dart:core\"}},"
+        "\"_kind\":\"RegularFunction\",\"static\":false,\"const\":false,"
+        "\"_intrinsic\":false,\"_native\":false,"
+        "\"location\":{\"type\":\"SourceLocation\","
+        "\"script\":{\"type\":\"@Script\",\"fixedId\":true,\"id\":\"\","
+        "\"uri\":\"dart:core\\/bool.dart\",\"_kind\":\"kernel\"},"
+        "\"tokenPos\":4372,\"endTokenPos\":4430}}",
         buffer);
   }
   // Library reference
@@ -4386,15 +4403,17 @@ ISOLATE_UNIT_TEST_CASE(PrintJSONPrimitives) {
     JSONStream js;
     Bool::True().PrintJSON(&js, true);
     ElideJSONSubstring("classes", js.ToCString(), buffer);
+    ElideJSONSubstring("libraries", buffer, buffer);
     EXPECT_STREQ(
-        "{\"type\":\"@Instance\","
-        "\"_vmType\":\"Bool\","
-        "\"class\":{\"type\":\"@Class\",\"fixedId\":true,\"id\":\"\","
-        "\"name\":\"bool\"},"
-        "\"identityHashCode\":0,"
-        "\"kind\":\"Bool\","
-        "\"fixedId\":true,"
-        "\"id\":\"objects\\/bool-true\",\"valueAsString\":\"true\"}",
+        "{\"type\":\"@Instance\",\"_vmType\":\"Bool\",\"class\":{\"type\":\"@"
+        "Class\",\"fixedId\":true,\"id\":\"\",\"name\":\"bool\",\"location\":{"
+        "\"type\":\"SourceLocation\",\"script\":{\"type\":\"@Script\","
+        "\"fixedId\":true,\"id\":\"\",\"uri\":\"dart:core\\/bool.dart\",\"_"
+        "kind\":\"kernel\"},\"tokenPos\":436,\"endTokenPos\":4432},\"library\":"
+        "{\"type\":\"@Library\",\"fixedId\":true,\"id\":\"\",\"name\":\"dart."
+        "core\",\"uri\":\"dart:core\"}},\"identityHashCode\":0,\"kind\":"
+        "\"Bool\",\"fixedId\":true,\"id\":\"objects\\/bool-true\","
+        "\"valueAsString\":\"true\"}",
         buffer);
   }
   // Smi reference
@@ -4404,16 +4423,17 @@ ISOLATE_UNIT_TEST_CASE(PrintJSONPrimitives) {
     smi.PrintJSON(&js, true);
     ElideJSONSubstring("classes", js.ToCString(), buffer);
     ElideJSONSubstring("_Smi@", buffer, buffer);
+    ElideJSONSubstring("libraries", buffer, buffer);
     EXPECT_STREQ(
-        "{\"type\":\"@Instance\","
-        "\"_vmType\":\"Smi\","
-        "\"class\":{\"type\":\"@Class\",\"fixedId\":true,\"id\":\"\","
-        "\"name\":\"_Smi\","
-        "\"_vmName\":\"\"},"
-        "\"identityHashCode\":0,"
-        "\"kind\":\"Int\","
-        "\"fixedId\":true,"
-        "\"id\":\"objects\\/int-7\",\"valueAsString\":\"7\"}",
+        "{\"type\":\"@Instance\",\"_vmType\":\"Smi\",\"class\":{\"type\":\"@"
+        "Class\",\"fixedId\":true,\"id\":\"\",\"name\":\"_Smi\",\"_vmName\":"
+        "\"\",\"location\":{\"type\":\"SourceLocation\",\"script\":{\"type\":"
+        "\"@Script\",\"fixedId\":true,\"id\":\"\",\"uri\":\"dart:core-"
+        "patch\\/integers.dart\",\"_kind\":\"kernel\"},\"tokenPos\":16466,"
+        "\"endTokenPos\":24948},\"library\":{\"type\":\"@Library\",\"fixedId\":"
+        "true,\"id\":\"\",\"name\":\"dart.core\",\"uri\":\"dart:core\"}},"
+        "\"identityHashCode\":0,\"kind\":\"Int\",\"fixedId\":true,\"id\":"
+        "\"objects\\/int-7\",\"valueAsString\":\"7\"}",
         buffer);
   }
   // Mint reference
@@ -4423,15 +4443,18 @@ ISOLATE_UNIT_TEST_CASE(PrintJSONPrimitives) {
     smi.PrintJSON(&js, true);
     ElideJSONSubstring("classes", js.ToCString(), buffer);
     ElideJSONSubstring("objects", buffer, buffer);
+    ElideJSONSubstring("libraries", buffer, buffer);
     ElideJSONSubstring("_Mint@", buffer, buffer);
     EXPECT_STREQ(
-        "{\"type\":\"@Instance\","
-        "\"_vmType\":\"Mint\","
-        "\"class\":{\"type\":\"@Class\",\"fixedId\":true,\"id\":\"\","
-        "\"name\":\"_Mint\",\"_vmName\":\"\"},"
-        "\"identityHashCode\":0,"
-        "\"kind\":\"Int\","
-        "\"id\":\"\",\"valueAsString\":\"-9223372036854775808\"}",
+        "{\"type\":\"@Instance\",\"_vmType\":\"Mint\",\"class\":{\"type\":\"@"
+        "Class\",\"fixedId\":true,\"id\":\"\",\"name\":\"_Mint\",\"_vmName\":"
+        "\"\",\"location\":{\"type\":\"SourceLocation\",\"script\":{\"type\":"
+        "\"@Script\",\"fixedId\":true,\"id\":\"\",\"uri\":\"dart:core-"
+        "patch\\/integers.dart\",\"_kind\":\"kernel\"},\"tokenPos\":25029,"
+        "\"endTokenPos\":25413},\"library\":{\"type\":\"@Library\",\"fixedId\":"
+        "true,\"id\":\"\",\"name\":\"dart.core\",\"uri\":\"dart:core\"}},"
+        "\"identityHashCode\":0,\"kind\":\"Int\",\"id\":\"\",\"valueAsString\":"
+        "\"-9223372036854775808\"}",
         buffer);
   }
   // Double reference
@@ -4441,15 +4464,18 @@ ISOLATE_UNIT_TEST_CASE(PrintJSONPrimitives) {
     dub.PrintJSON(&js, true);
     ElideJSONSubstring("classes", js.ToCString(), buffer);
     ElideJSONSubstring("objects", buffer, buffer);
+    ElideJSONSubstring("libraries", buffer, buffer);
     ElideJSONSubstring("_Double@", buffer, buffer);
     EXPECT_STREQ(
-        "{\"type\":\"@Instance\","
-        "\"_vmType\":\"Double\","
-        "\"class\":{\"type\":\"@Class\",\"fixedId\":true,\"id\":\"\","
-        "\"name\":\"_Double\",\"_vmName\":\"\"},"
-        "\"identityHashCode\":0,"
-        "\"kind\":\"Double\","
-        "\"id\":\"\",\"valueAsString\":\"0.1234\"}",
+        "{\"type\":\"@Instance\",\"_vmType\":\"Double\",\"class\":{\"type\":\"@"
+        "Class\",\"fixedId\":true,\"id\":\"\",\"name\":\"_Double\",\"_vmName\":"
+        "\"\",\"location\":{\"type\":\"SourceLocation\",\"script\":{\"type\":"
+        "\"@Script\",\"fixedId\":true,\"id\":\"\",\"uri\":\"dart:core-"
+        "patch\\/double.dart\",\"_kind\":\"kernel\"},\"tokenPos\":248,"
+        "\"endTokenPos\":12248},\"library\":{\"type\":\"@Library\",\"fixedId\":"
+        "true,\"id\":\"\",\"name\":\"dart.core\",\"uri\":\"dart:core\"}},"
+        "\"identityHashCode\":0,\"kind\":\"Double\",\"id\":\"\","
+        "\"valueAsString\":\"0.1234\"}",
         buffer);
   }
   // String reference
@@ -4459,15 +4485,18 @@ ISOLATE_UNIT_TEST_CASE(PrintJSONPrimitives) {
     str.PrintJSON(&js, true);
     ElideJSONSubstring("classes", js.ToCString(), buffer);
     ElideJSONSubstring("objects", buffer, buffer);
+    ElideJSONSubstring("libraries", buffer, buffer);
     ElideJSONSubstring("_OneByteString@", buffer, buffer);
     EXPECT_STREQ(
-        "{\"type\":\"@Instance\","
-        "\"_vmType\":\"String\","
-        "\"class\":{\"type\":\"@Class\",\"fixedId\":true,\"id\":\"\","
-        "\"name\":\"_OneByteString\",\"_vmName\":\"\"},"
-        "\"identityHashCode\":0,"
-        "\"kind\":\"String\","
-        "\"id\":\"\",\"length\":2,\"valueAsString\":\"dw\"}",
+        "{\"type\":\"@Instance\",\"_vmType\":\"String\",\"class\":{\"type\":\"@"
+        "Class\",\"fixedId\":true,\"id\":\"\",\"name\":\"_OneByteString\",\"_"
+        "vmName\":\"\",\"location\":{\"type\":\"SourceLocation\",\"script\":{"
+        "\"type\":\"@Script\",\"fixedId\":true,\"id\":\"\",\"uri\":\"dart:core-"
+        "patch\\/string_patch.dart\",\"_kind\":\"kernel\"},\"tokenPos\":32310,"
+        "\"endTokenPos\":44332},\"library\":{\"type\":\"@Library\",\"fixedId\":"
+        "true,\"id\":\"\",\"name\":\"dart.core\",\"uri\":\"dart:core\"}},"
+        "\"identityHashCode\":0,\"kind\":\"String\",\"id\":\"\",\"length\":2,"
+        "\"valueAsString\":\"dw\"}",
         buffer);
   }
   // Array reference
@@ -4477,15 +4506,17 @@ ISOLATE_UNIT_TEST_CASE(PrintJSONPrimitives) {
     array.PrintJSON(&js, true);
     ElideJSONSubstring("classes", js.ToCString(), buffer);
     ElideJSONSubstring("objects", buffer, buffer);
+    ElideJSONSubstring("libraries", buffer, buffer);
     ElideJSONSubstring("_List@", buffer, buffer);
     EXPECT_STREQ(
-        "{\"type\":\"@Instance\","
-        "\"_vmType\":\"Array\","
-        "\"class\":{\"type\":\"@Class\",\"fixedId\":true,\"id\":\"\","
-        "\"name\":\"_List\",\"_vmName\":\"\"},"
-        "\"identityHashCode\":0,"
-        "\"kind\":\"List\","
-        "\"id\":\"\",\"length\":0}",
+        "{\"type\":\"@Instance\",\"_vmType\":\"Array\",\"class\":{\"type\":\"@"
+        "Class\",\"fixedId\":true,\"id\":\"\",\"name\":\"_List\",\"_vmName\":"
+        "\"\",\"location\":{\"type\":\"SourceLocation\",\"script\":{\"type\":"
+        "\"@Script\",\"fixedId\":true,\"id\":\"\",\"uri\":\"dart:core-"
+        "patch\\/array.dart\",\"_kind\":\"kernel\"},\"tokenPos\":248,"
+        "\"endTokenPos\":7758},\"library\":{\"type\":\"@Library\",\"fixedId\":"
+        "true,\"id\":\"\",\"name\":\"dart.core\",\"uri\":\"dart:core\"}},"
+        "\"identityHashCode\":0,\"kind\":\"List\",\"id\":\"\",\"length\":0}",
         buffer);
   }
   // GrowableObjectArray reference
@@ -4496,16 +4527,18 @@ ISOLATE_UNIT_TEST_CASE(PrintJSONPrimitives) {
     array.PrintJSON(&js, true);
     ElideJSONSubstring("classes", js.ToCString(), buffer);
     ElideJSONSubstring("objects", buffer, buffer);
+    ElideJSONSubstring("libraries", buffer, buffer);
     ElideJSONSubstring("_GrowableList@", buffer, buffer);
     EXPECT_STREQ(
-        "{\"type\":\"@Instance\","
-        "\"_vmType\":\"GrowableObjectArray\","
-        "\"class\":{\"type\":\"@Class\",\"fixedId\":true,\"id\":\"\","
-        "\"name\":\"_GrowableList\","
-        "\"_vmName\":\"\"},"
-        "\"identityHashCode\":0,"
-        "\"kind\":\"List\","
-        "\"id\":\"\",\"length\":0}",
+        "{\"type\":\"@Instance\",\"_vmType\":\"GrowableObjectArray\",\"class\":"
+        "{\"type\":\"@Class\",\"fixedId\":true,\"id\":\"\",\"name\":\"_"
+        "GrowableList\",\"_vmName\":\"\",\"location\":{\"type\":"
+        "\"SourceLocation\",\"script\":{\"type\":\"@Script\",\"fixedId\":true,"
+        "\"id\":\"\",\"uri\":\"dart:core-patch\\/growable_array.dart\",\"_"
+        "kind\":\"kernel\"},\"tokenPos\":248,\"endTokenPos\":18485},"
+        "\"library\":{\"type\":\"@Library\",\"fixedId\":true,\"id\":\"\","
+        "\"name\":\"dart.core\",\"uri\":\"dart:core\"}},\"identityHashCode\":0,"
+        "\"kind\":\"List\",\"id\":\"\",\"length\":0}",
         buffer);
   }
   // LinkedHashMap reference
@@ -4516,15 +4549,18 @@ ISOLATE_UNIT_TEST_CASE(PrintJSONPrimitives) {
     array.PrintJSON(&js, true);
     ElideJSONSubstring("classes", js.ToCString(), buffer);
     ElideJSONSubstring("objects", buffer, buffer);
+    ElideJSONSubstring("libraries", buffer, buffer);
     ElideJSONSubstring("_InternalLinkedHashMap@", buffer, buffer);
     EXPECT_STREQ(
-        "{\"type\":\"@Instance\","
-        "\"_vmType\":\"LinkedHashMap\","
-        "\"class\":{\"type\":\"@Class\",\"fixedId\":true,\"id\":\"\","
-        "\"name\":\"_InternalLinkedHashMap\",\"_vmName\":\"\"},"
-        "\"identityHashCode\":0,"
-        "\"kind\":\"Map\","
-        "\"id\":\"\","
+        "{\"type\":\"@Instance\",\"_vmType\":\"LinkedHashMap\",\"class\":{"
+        "\"type\":\"@Class\",\"fixedId\":true,\"id\":\"\",\"name\":\"_"
+        "InternalLinkedHashMap\",\"_vmName\":\"\",\"location\":{\"type\":"
+        "\"SourceLocation\",\"script\":{\"type\":\"@Script\",\"fixedId\":true,"
+        "\"id\":\"\",\"uri\":\"dart:collection-patch\\/"
+        "compact_hash.dart\",\"_kind\":\"kernel\"},\"tokenPos\":6399,"
+        "\"endTokenPos\":6786},\"library\":{\"type\":\"@Library\",\"fixedId\":"
+        "true,\"id\":\"\",\"name\":\"dart.collection\",\"uri\":\"dart:"
+        "collection\"}},\"identityHashCode\":0,\"kind\":\"Map\",\"id\":\"\","
         "\"length\":0}",
         buffer);
   }
@@ -4535,12 +4571,17 @@ ISOLATE_UNIT_TEST_CASE(PrintJSONPrimitives) {
     tag.PrintJSON(&js, true);
     ElideJSONSubstring("classes", js.ToCString(), buffer);
     ElideJSONSubstring("objects", buffer, buffer);
+    ElideJSONSubstring("libraries", buffer, buffer);
     ElideJSONSubstring("_UserTag@", buffer, buffer);
     EXPECT_SUBSTRING(
-        "{\"type\":\"@Instance\","
-        "\"_vmType\":\"UserTag\","
-        "\"class\":{\"type\":\"@Class\",\"fixedId\":true,\"id\":\"\","
-        "\"name\":\"_UserTag\",\"_vmName\":\"\"},"
+        "\"type\":\"@Instance\",\"_vmType\":\"UserTag\",\"class\":{\"type\":\"@"
+        "Class\",\"fixedId\":true,\"id\":\"\",\"name\":\"_UserTag\",\"_"
+        "vmName\":\"\",\"location\":{\"type\":\"SourceLocation\",\"script\":{"
+        "\"type\":\"@Script\",\"fixedId\":true,\"id\":\"\",\"uri\":\"dart:"
+        "developer-patch\\/profiler.dart\",\"_kind\":\"kernel\"},\"tokenPos\":"
+        "414,\"endTokenPos\":672},\"library\":{\"type\":\"@Library\","
+        "\"fixedId\":true,\"id\":\"\",\"name\":\"dart.developer\",\"uri\":"
+        "\"dart:developer\"}},"
         // Handle non-zero identity hash.
         "\"identityHashCode\":",
         buffer);
@@ -4558,12 +4599,16 @@ ISOLATE_UNIT_TEST_CASE(PrintJSONPrimitives) {
     type.PrintJSON(&js, true);
     ElideJSONSubstring("classes", js.ToCString(), buffer);
     ElideJSONSubstring("objects", buffer, buffer);
+    ElideJSONSubstring("libraries", buffer, buffer);
     ElideJSONSubstring("_Type@", buffer, buffer);
     EXPECT_SUBSTRING(
-        "{\"type\":\"@Instance\","
-        "\"_vmType\":\"Type\","
-        "\"class\":{\"type\":\"@Class\",\"fixedId\":true,\"id\":\"\","
-        "\"name\":\"_Type\",\"_vmName\":\"\"},"
+        "{\"type\":\"@Instance\",\"_vmType\":\"Type\",\"class\":{\"type\":\"@"
+        "Class\",\"fixedId\":true,\"id\":\"\",\"name\":\"_Type\",\"_vmName\":"
+        "\"\",\"location\":{\"type\":\"SourceLocation\",\"script\":{\"type\":"
+        "\"@Script\",\"fixedId\":true,\"id\":\"\",\"uri\":\"dart:core-"
+        "patch\\/type_patch.dart\",\"_kind\":\"kernel\"},\"tokenPos\":493,"
+        "\"endTokenPos\":898},\"library\":{\"type\":\"@Library\",\"fixedId\":"
+        "true,\"id\":\"\",\"name\":\"dart.core\",\"uri\":\"dart:core\"}},"
         // Handle non-zero identity hash.
         "\"identityHashCode\":",
         buffer);
@@ -4571,7 +4616,12 @@ ISOLATE_UNIT_TEST_CASE(PrintJSONPrimitives) {
         "\"kind\":\"Type\","
         "\"fixedId\":true,\"id\":\"\","
         "\"typeClass\":{\"type\":\"@Class\",\"fixedId\":true,\"id\":\"\","
-        "\"name\":\"bool\"},\"name\":\"bool\"}",
+        "\"name\":\"bool\",\"location\":{\"type\":\"SourceLocation\","
+        "\"script\":{\"type\":\"@Script\",\"fixedId\":true,\"id\":\"\",\"uri\":"
+        "\"dart:core\\/bool.dart\",\"_kind\":\"kernel\"},\"tokenPos\":436,"
+        "\"endTokenPos\":4432},\"library\":{\"type\":\"@Library\",\"fixedId\":"
+        "true,\"id\":\"\",\"name\":\"dart.core\",\"uri\":\"dart:core\"}},"
+        "\"name\":\"bool\"}",
         buffer);
   }
   // Null reference
@@ -4579,15 +4629,16 @@ ISOLATE_UNIT_TEST_CASE(PrintJSONPrimitives) {
     JSONStream js;
     Object::null_object().PrintJSON(&js, true);
     ElideJSONSubstring("classes", js.ToCString(), buffer);
+    ElideJSONSubstring("libraries", buffer, buffer);
     EXPECT_STREQ(
-        "{\"type\":\"@Instance\","
-        "\"_vmType\":\"null\","
-        "\"class\":{\"type\":\"@Class\",\"fixedId\":true,\"id\":\"\","
-        "\"name\":\"Null\"},"
-        "\"kind\":\"Null\","
-        "\"fixedId\":true,"
-        "\"id\":\"objects\\/null\","
-        "\"valueAsString\":\"null\"}",
+        "{\"type\":\"@Instance\",\"_vmType\":\"null\",\"class\":{\"type\":\"@"
+        "Class\",\"fixedId\":true,\"id\":\"\",\"name\":\"Null\",\"location\":{"
+        "\"type\":\"SourceLocation\",\"script\":{\"type\":\"@Script\","
+        "\"fixedId\":true,\"id\":\"\",\"uri\":\"dart:core\\/null.dart\",\"_"
+        "kind\":\"kernel\"},\"tokenPos\":925,\"endTokenPos\":1165},\"library\":"
+        "{\"type\":\"@Library\",\"fixedId\":true,\"id\":\"\",\"name\":\"dart."
+        "core\",\"uri\":\"dart:core\"}},\"kind\":\"Null\",\"fixedId\":true,"
+        "\"id\":\"objects\\/null\",\"valueAsString\":\"null\"}",
         buffer);
   }
   // Sentinel reference
diff --git a/runtime/vm/service.h b/runtime/vm/service.h
index 0b94d3d6258..390eee41879 100644
--- a/runtime/vm/service.h
+++ b/runtime/vm/service.h
@@ -15,7 +15,7 @@
 namespace dart {
 
 #define SERVICE_PROTOCOL_MAJOR_VERSION 3
-#define SERVICE_PROTOCOL_MINOR_VERSION 45
+#define SERVICE_PROTOCOL_MINOR_VERSION 46
 
 class Array;
 class EmbedderServiceHandler;
diff --git a/runtime/vm/service/service.md b/runtime/vm/service/service.md
index bfbf6571e10..c0d874a9f94 100644
--- a/runtime/vm/service/service.md
+++ b/runtime/vm/service/service.md
@@ -1,8 +1,8 @@
-# Dart VM Service Protocol 3.45
+# Dart VM Service Protocol 3.46
 
 > Please post feedback to the [observatory-discuss group][discuss-list]
 
-This document describes of _version 3.45_ of the Dart VM Service Protocol. This
+This document describes of _version 3.46_ of the Dart VM Service Protocol. This
 protocol is used to communicate with a running Dart Virtual Machine.
 
 To use the Service Protocol, start the VM with the *--observe* flag.
@@ -1687,6 +1687,12 @@ been loaded (i.e. a deferred library).
 class @Class extends @Object {
   // The name of this class.
   string name;
+
+  // The location of this class in the source code.
+  SourceLocation location [optional];
+
+  // The library which contains this class.
+  @Library library;
 }
 ```
 
@@ -1697,6 +1703,12 @@ class Class extends Object {
   // The name of this class.
   string name;
 
+  // The location of this class in the source code.
+  SourceLocation location [optional];
+
+  // The library which contains this class.
+  @Library library;
+
   // The error which occurred during class finalization, if it exists.
   @Error error [optional];
 
@@ -1709,12 +1721,6 @@ class Class extends Object {
   // Are allocations of this class being traced?
   bool traceAllocations;
 
-  // The library which contains this class.
-  @Library library;
-
-  // The location of this class in the source code.
-  SourceLocation location [optional];
-
   // The superclass of this class, if any.
   @Class super [optional];
 
@@ -2298,6 +2304,9 @@ class @Field extends @Object {
 
   // Is this field static?
   bool static;
+
+  // The location of this field in the source code.
+  SourceLocation location [optional];
 }
 ```
 
@@ -2327,12 +2336,12 @@ class Field extends Object {
   // Is this field static?
   bool static;
 
+  // The location of this field in the source code.
+  SourceLocation location [optional];
+
   // The value of this field, if the field is static. If uninitialized,
   // this will take the value of an uninitialized Sentinel.
   @Instance|Sentinel staticValue [optional];
-
-  // The location of this field in the source code.
-  SourceLocation location [optional];
 }
 ```
 
@@ -2401,6 +2410,9 @@ class @Function extends @Object {
 
   // Is this function const?
   bool const;
+
+  // The location of this function in the source code.
+  SourceLocation location [optional];
 }
 ```
 
@@ -4038,5 +4050,6 @@ version | comments
 3.43 | Updated heap snapshot format to include identity hash codes. Added `getAllocationTraces` and `setTraceClassAllocation` RPCs, updated `CpuSample` to include `identityHashCode` and `classId` properties, updated `Class` to include `traceAllocations` property.
 3.44 | Added `identityHashCode` property to `@Instance` and `Instance`.
 3.45 | Added `setBreakpointState` RPC and `BreakpointUpdated` event kind.
+3.46 | Moved `sourceLocation` property into reference types for `Class`, `Field`, and `Function`.
 
 [discuss-list]: https://groups.google.com/a/dartlang.org/forum/#!forum/observatory-discuss
diff --git a/runtime/vm/source_report_test.cc b/runtime/vm/source_report_test.cc
index 9bc1aac859e..f7314c0f803 100644
--- a/runtime/vm/source_report_test.cc
+++ b/runtime/vm/source_report_test.cc
@@ -501,7 +501,10 @@ ISOLATE_UNIT_TEST_CASE(SourceReport_CallSites_SimpleCall) {
       "\"name\":\"helper0\",\"owner\":{\"type\":\"@Library\",\"fixedId\":true,"
       "\"id\":\"\",\"name\":\"\",\"uri\":\"file:\\/\\/\\/test-lib\"},"
       "\"_kind\":\"RegularFunction\",\"static\":true,\"const\":false,"
-      "\"_intrinsic\":false,\"_native\":false},\"count\":1}]}]}],"
+      "\"_intrinsic\":false,\"_native\":false,\"location\":{\"type\":"
+      "\"SourceLocation\",\"script\":{\"type\":\"@Script\",\"fixedId\":true,"
+      "\"id\":\"\",\"uri\":\"file:\\/\\/\\/test-lib\",\"_kind\":\"kernel\"},"
+      "\"tokenPos\":0,\"endTokenPos\":11}},\"count\":1}]}]}],"
 
       // One script in the script table.
       "\"scripts\":[{\"type\":\"@Script\",\"fixedId\":true,\"id\":\"\","
@@ -510,7 +513,7 @@ ISOLATE_UNIT_TEST_CASE(SourceReport_CallSites_SimpleCall) {
 }
 
 ISOLATE_UNIT_TEST_CASE(SourceReport_CallSites_PolymorphicCall) {
-  char buffer[1024];
+  char buffer[4096];
   const char* kScript =
       "class Common {\n"
       "  func() {}\n"
@@ -553,27 +556,65 @@ ISOLATE_UNIT_TEST_CASE(SourceReport_CallSites_PolymorphicCall) {
 
       // First receiver: "Common", called twice.
       "{\"receiver\":{\"type\":\"@Class\",\"fixedId\":true,\"id\":\"\","
-      "\"name\":\"Common\"},"
+      "\"name\":\"Common\","
+      "\"location\":{\"type\":\"SourceLocation\","
+      "\"script\":{\"type\":\"@Script\","
+      "\"fixedId\":true,\"id\":\"\","
+      "\"uri\":\"file:\\/\\/\\/test-lib\","
+      "\"_kind\":\"kernel\"},\"tokenPos\":0,\"endTokenPos\":27},"
+      "\"library\":{\"type\":\"@Library\",\"fixedId\":true,"
+      "\"id\":\"\",\"name\":\"\",\"uri\":\"file:\\/\\/\\/test-lib\"}},"
 
       "\"target\":{\"type\":\"@Function\",\"fixedId\":true,\"id\":\"\","
       "\"name\":\"func\","
       "\"owner\":{\"type\":\"@Class\",\"fixedId\":true,\"id\":\"\","
-      "\"name\":\"Common\"},\"_kind\":\"RegularFunction\","
+      "\"name\":\"Common\","
+      "\"location\":{\"type\":\"SourceLocation\","
+      "\"script\":{\"type\":\"@Script\","
+      "\"fixedId\":true,\"id\":\"\","
+      "\"uri\":\"file:\\/\\/\\/test-lib\","
+      "\"_kind\":\"kernel\"},\"tokenPos\":0,\"endTokenPos\":27},"
+      "\"library\":{\"type\":\"@Library\",\"fixedId\":true,"
+      "\"id\":\"\",\"name\":\"\",\"uri\":\"file:\\/\\/\\/test-lib\"}"
+      "},\"_kind\":\"RegularFunction\","
       "\"static\":false,\"const\":false,\"_intrinsic\":false,"
-      "\"_native\":false},"
+      "\"_native\":false,"
+      "\"location\":{\"type\":\"SourceLocation\","
+      "\"script\":{\"type\":\"@Script\",\"fixedId\":true,"
+      "\"id\":\"\",\"uri\":\"file:\\/\\/\\/test-lib\","
+      "\"_kind\":\"kernel\"},\"tokenPos\":17,\"endTokenPos\":25}},"
 
       "\"count\":2},"
 
       // Second receiver: "Uncommon", called once.
       "{\"receiver\":{\"type\":\"@Class\",\"fixedId\":true,\"id\":\"\","
-      "\"name\":\"Uncommon\"},"
+      "\"name\":\"Uncommon\","
+      "\"location\":{\"type\":\"SourceLocation\","
+      "\"script\":{\"type\":\"@Script\","
+      "\"fixedId\":true,\"id\":\"\","
+      "\"uri\":\"file:\\/\\/\\/test-lib\","
+      "\"_kind\":\"kernel\"},\"tokenPos\":29,\"endTokenPos\":58},"
+      "\"library\":{\"type\":\"@Library\",\"fixedId\":true,"
+      "\"id\":\"\",\"name\":\"\",\"uri\":\"file:\\/\\/\\/test-lib\"}},"
 
       "\"target\":{\"type\":\"@Function\",\"fixedId\":true,\"id\":\"\","
       "\"name\":\"func\","
       "\"owner\":{\"type\":\"@Class\",\"fixedId\":true,\"id\":\"\","
-      "\"name\":\"Uncommon\"},\"_kind\":\"RegularFunction\","
+      "\"name\":\"Uncommon\","
+      "\"location\":{\"type\":\"SourceLocation\","
+      "\"script\":{\"type\":\"@Script\","
+      "\"fixedId\":true,\"id\":\"\","
+      "\"uri\":\"file:\\/\\/\\/test-lib\","
+      "\"_kind\":\"kernel\"},\"tokenPos\":29,\"endTokenPos\":58},"
+      "\"library\":{\"type\":\"@Library\",\"fixedId\":true,"
+      "\"id\":\"\",\"name\":\"\",\"uri\":\"file:\\/\\/\\/test-lib\"}"
+      "},\"_kind\":\"RegularFunction\","
       "\"static\":false,\"const\":false,\"_intrinsic\":false,"
-      "\"_native\":false},"
+      "\"_native\":false,"
+      "\"location\":{\"type\":\"SourceLocation\","
+      "\"script\":{\"type\":\"@Script\",\"fixedId\":true,"
+      "\"id\":\"\",\"uri\":\"file:\\/\\/\\/test-lib\","
+      "\"_kind\":\"kernel\"},\"tokenPos\":48,\"endTokenPos\":56}},"
 
       "\"count\":1}]}]}],"
 
@@ -584,7 +625,7 @@ ISOLATE_UNIT_TEST_CASE(SourceReport_CallSites_PolymorphicCall) {
 }
 
 ISOLATE_UNIT_TEST_CASE(SourceReport_MultipleReports) {
-  char buffer[1024];
+  char buffer[2048];
   const char* kScript =
       "helper0() {}\n"
       "helper1() {}\n"
@@ -614,16 +655,18 @@ ISOLATE_UNIT_TEST_CASE(SourceReport_MultipleReports) {
       // One range not compiled (helper1).
       "{\"scriptIndex\":0,\"startPos\":13,\"endPos\":24,\"compiled\":false},"
 
-      // One range compiled with one callsite (main).
+      // One range compiled with one callsite (main)m
       "{\"scriptIndex\":0,\"startPos\":26,\"endPos\":48,\"compiled\":true,"
-      "\"callSites\":["
-      "{\"name\":\"helper0\",\"tokenPos\":37,\"cacheEntries\":["
-      "{\"target\":{\"type\":\"@Function\",\"fixedId\":true,\"id\":\"\","
+      "\"callSites\":[{\"name\":\"helper0\",\"tokenPos\":37,\"cacheEntries\":[{"
+      "\"target\":{\"type\":\"@Function\",\"fixedId\":true,\"id\":\"\","
       "\"name\":\"helper0\",\"owner\":{\"type\":\"@Library\",\"fixedId\":true,"
-      "\"id\":\"\",\"name\":\"\",\"uri\":\"file:\\/\\/\\/test-lib\"},"
-      "\"_kind\":\"RegularFunction\",\"static\":true,\"const\":false,"
-      "\"_intrinsic\":false,\"_native\":false},\"count\":1}]}],"
-      "\"coverage\":{\"hits\":[26,37],\"misses\":[]}}],"
+      "\"id\":\"\",\"name\":\"\",\"uri\":\"file:\\/\\/\\/test-lib\"},\"_"
+      "kind\":\"RegularFunction\",\"static\":true,\"const\":false,\"_"
+      "intrinsic\":false,\"_native\":false,\"location\":{\"type\":"
+      "\"SourceLocation\",\"script\":{\"type\":\"@Script\",\"fixedId\":true,"
+      "\"id\":\"\",\"uri\":\"file:\\/\\/\\/test-lib\",\"_kind\":\"kernel\"},"
+      "\"tokenPos\":0,\"endTokenPos\":11}},\"count\":1}]}],\"coverage\":{"
+      "\"hits\":[26,37],\"misses\":[]}}],"
 
       // One script in the script table.
       "\"scripts\":[{\"type\":\"@Script\",\"fixedId\":true,\"id\":\"\","
diff --git a/third_party/devtools/update.sh b/third_party/devtools/update.sh
index 077d758c333..ae3aa496f60 100755
--- a/third_party/devtools/update.sh
+++ b/third_party/devtools/update.sh
@@ -36,5 +36,6 @@ cipd create \
   -name dart/third_party/flutter/devtools \
   -in cipd_package \
   -install-mode copy \
+  -preserve-writable \
   -tag git_revision:$1