fix: Context parse error, parent should be ContextRef

Bug: https://github.com/dart-lang/sdk/issues/45083
TEST=N/A
Change-Id: I1781c83ac2e8868f1d6a49fc4a01edd3e3eef460
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/192880
Reviewed-by: Ben Konyi <bkonyi@google.com>
Commit-Queue: Ben Konyi <bkonyi@google.com>

pkg/vm_service/CHANGELOG.md

@@ -1,6 +1,6 @@
 # Changelog
-
-## 6.3.0-dev
+## 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
   `enabled` property.
 

pkg/vm_service/lib/src/vm_service.dart

@@ -3318,7 +3318,7 @@ class Context extends Obj implements ContextRef {
 
   /// The enclosing context for this context.
   @optional
-  Context? parent;
+  ContextRef? parent;
 
   /// The variables in this context object.
   List<ContextElement>? variables;
@@ -3334,7 +3334,8 @@ class Context extends Obj implements ContextRef {
 
   Context._fromJson(Map<String, dynamic> json) : super._fromJson(json) {
     length = json['length'] ?? -1;
-    parent = createServiceObject(json['parent'], const ['Context']) as Context?;
+    parent = createServiceObject(json['parent'], const ['ContextRef'])
+        as ContextRef?;
     variables = List<ContextElement>.from(
         createServiceObject(json['variables'], const ['ContextElement'])
                 as List? ??

pkg/vm_service/pubspec.yaml

@@ -3,7 +3,7 @@ description: >-
   A library to communicate with a service implementing the Dart VM
   service protocol.
 
-version: 6.3.0-dev
+version: 7.0.0
 
 homepage: https://github.com/dart-lang/sdk/tree/master/pkg/vm_service
 

runtime/vm/service/service.md

@@ -1832,7 +1832,7 @@ class Context extends Object {
   int length;
 
   // The enclosing context for this context.
-  Context parent [optional];
+  @Context parent [optional];
 
   // The variables in this context object.
   ContextElement[] variables;