diff --git a/pkg/front_end/testcases/expression/beyond_dart_semantics_03.expression.yaml b/pkg/front_end/testcases/expression/beyond_dart_semantics_03.expression.yaml
index 7a08b340abe..9c553ff9504 100644
--- a/pkg/front_end/testcases/expression/beyond_dart_semantics_03.expression.yaml
+++ b/pkg/front_end/testcases/expression/beyond_dart_semantics_03.expression.yaml
@@ -49,7 +49,7 @@ type_bounds: []
 type_defaults: []
 method: "foo"
 static: true
-offset: 94
+offset: 108
 scriptUri: main.dart
 expression: |
   list.first._value
diff --git a/pkg/front_end/testcases/expression/beyond_dart_semantics_03.expression.yaml.expect b/pkg/front_end/testcases/expression/beyond_dart_semantics_03.expression.yaml.expect
index 1da3716a9df..bd7731fde7e 100644
--- a/pkg/front_end/testcases/expression/beyond_dart_semantics_03.expression.yaml.expect
+++ b/pkg/front_end/testcases/expression/beyond_dart_semantics_03.expression.yaml.expect
@@ -1,4 +1,4 @@
 Errors: {
 }
-static method /* from org-dartlang-debug:synthetic_debug_expression */ debugExpr(dart.core::_GrowableList<main::A> list) → dynamic
-  return list.{dart.core::_GrowableList::first}{main::A}{dynamic}.lib::_value;
+static method /* from org-dartlang-debug:synthetic_debug_expression */ debugExpr(dart.core::List<main::A> list) → dynamic
+  return list.{dart.core::Iterable::first}{main::A}{dynamic}.lib::_value;
diff --git a/pkg/front_end/testcases/expression/beyond_dart_semantics_03_prime.expression.yaml b/pkg/front_end/testcases/expression/beyond_dart_semantics_03_prime.expression.yaml
index 39a7242bf87..5cf2d90e0f1 100644
--- a/pkg/front_end/testcases/expression/beyond_dart_semantics_03_prime.expression.yaml
+++ b/pkg/front_end/testcases/expression/beyond_dart_semantics_03_prime.expression.yaml
@@ -57,7 +57,7 @@ type_bounds: []
 type_defaults: []
 method: "foo"
 static: true
-offset: 94
+offset: 129
 scriptUri: main.dart
 expression: |
   list.first._value
diff --git a/pkg/front_end/testcases/expression/beyond_dart_semantics_03_prime.expression.yaml.expect b/pkg/front_end/testcases/expression/beyond_dart_semantics_03_prime.expression.yaml.expect
index b50d3c244e2..69491d4fe5e 100644
--- a/pkg/front_end/testcases/expression/beyond_dart_semantics_03_prime.expression.yaml.expect
+++ b/pkg/front_end/testcases/expression/beyond_dart_semantics_03_prime.expression.yaml.expect
@@ -1,4 +1,4 @@
 Errors: {
 }
-static method /* from org-dartlang-debug:synthetic_debug_expression */ debugExpr(dart.core::_GrowableList<main::A> list) → dynamic
-  return list.{dart.core::_GrowableList::first}{main::A}{dynamic}._value;
+static method /* from org-dartlang-debug:synthetic_debug_expression */ debugExpr(dart.core::List<main::A> list) → dynamic
+  return list.{dart.core::Iterable::first}{main::A}{dynamic}._value;
diff --git a/pkg/front_end/testcases/expression/beyond_dart_semantics_04.expression.yaml b/pkg/front_end/testcases/expression/beyond_dart_semantics_04.expression.yaml
index 4f5ab6ec92d..77be0909ebb 100644
--- a/pkg/front_end/testcases/expression/beyond_dart_semantics_04.expression.yaml
+++ b/pkg/front_end/testcases/expression/beyond_dart_semantics_04.expression.yaml
@@ -49,7 +49,7 @@ type_bounds: []
 type_defaults: []
 method: "foo"
 static: true
-offset: 94
+offset: 132
 scriptUri: main.dart
 expression: |
   list.first._value = 41
diff --git a/pkg/front_end/testcases/expression/beyond_dart_semantics_04.expression.yaml.expect b/pkg/front_end/testcases/expression/beyond_dart_semantics_04.expression.yaml.expect
index dc393b65290..90705a2ec9f 100644
--- a/pkg/front_end/testcases/expression/beyond_dart_semantics_04.expression.yaml.expect
+++ b/pkg/front_end/testcases/expression/beyond_dart_semantics_04.expression.yaml.expect
@@ -1,4 +1,4 @@
 Errors: {
 }
-static method /* from org-dartlang-debug:synthetic_debug_expression */ debugExpr(dart.core::_GrowableList<main::A> list) → dynamic
-  return list.{dart.core::_GrowableList::first}{main::A}.{dynamic}lib::_value = 41;
+static method /* from org-dartlang-debug:synthetic_debug_expression */ debugExpr(dart.core::List<main::A> list) → dynamic
+  return list.{dart.core::Iterable::first}{main::A}.{dynamic}lib::_value = 41;
diff --git a/pkg/front_end/testcases/expression/beyond_dart_semantics_05.expression.yaml b/pkg/front_end/testcases/expression/beyond_dart_semantics_05.expression.yaml
index 86ba8cb307a..9098c068afc 100644
--- a/pkg/front_end/testcases/expression/beyond_dart_semantics_05.expression.yaml
+++ b/pkg/front_end/testcases/expression/beyond_dart_semantics_05.expression.yaml
@@ -46,7 +46,7 @@ type_bounds: []
 type_defaults: []
 method: "foo"
 static: true
-offset: 94
+offset: 108
 scriptUri: main.dart
 expression: |
   list.first.hello()
diff --git a/pkg/front_end/testcases/expression/beyond_dart_semantics_05.expression.yaml.expect b/pkg/front_end/testcases/expression/beyond_dart_semantics_05.expression.yaml.expect
index 81d5f443de9..c9a8ec5399a 100644
--- a/pkg/front_end/testcases/expression/beyond_dart_semantics_05.expression.yaml.expect
+++ b/pkg/front_end/testcases/expression/beyond_dart_semantics_05.expression.yaml.expect
@@ -1,4 +1,4 @@
 Errors: {
 }
-static method /* from org-dartlang-debug:synthetic_debug_expression */ debugExpr(dart.core::_GrowableList<main::A> list) → dynamic
-  return list.{dart.core::_GrowableList::first}{main::A}{dynamic}.hello();
+static method /* from org-dartlang-debug:synthetic_debug_expression */ debugExpr(dart.core::List<main::A> list) → dynamic
+  return list.{dart.core::Iterable::first}{main::A}{dynamic}.hello();
diff --git a/pkg/front_end/testcases/expression/beyond_dart_semantics_06.expression.yaml b/pkg/front_end/testcases/expression/beyond_dart_semantics_06.expression.yaml
index dfa96448aca..e29cc27e3e3 100644
--- a/pkg/front_end/testcases/expression/beyond_dart_semantics_06.expression.yaml
+++ b/pkg/front_end/testcases/expression/beyond_dart_semantics_06.expression.yaml
@@ -46,7 +46,7 @@ type_bounds: []
 type_defaults: []
 method: "foo"
 static: true
-offset: 94
+offset: 108
 scriptUri: main.dart
 expression: |
   list.first._hello()
diff --git a/pkg/front_end/testcases/expression/beyond_dart_semantics_06.expression.yaml.expect b/pkg/front_end/testcases/expression/beyond_dart_semantics_06.expression.yaml.expect
index 795381c2443..48e55067e43 100644
--- a/pkg/front_end/testcases/expression/beyond_dart_semantics_06.expression.yaml.expect
+++ b/pkg/front_end/testcases/expression/beyond_dart_semantics_06.expression.yaml.expect
@@ -1,4 +1,4 @@
 Errors: {
 }
-static method /* from org-dartlang-debug:synthetic_debug_expression */ debugExpr(dart.core::_GrowableList<main::A> list) → dynamic
-  return list.{dart.core::_GrowableList::first}{main::A}{dynamic}.lib::_hello();
+static method /* from org-dartlang-debug:synthetic_debug_expression */ debugExpr(dart.core::List<main::A> list) → dynamic
+  return list.{dart.core::Iterable::first}{main::A}{dynamic}.lib::_hello();
diff --git a/pkg/front_end/testcases/expression/beyond_dart_semantics_07.expression.yaml b/pkg/front_end/testcases/expression/beyond_dart_semantics_07.expression.yaml
index ffcfecf3852..61919c0b40d 100644
--- a/pkg/front_end/testcases/expression/beyond_dart_semantics_07.expression.yaml
+++ b/pkg/front_end/testcases/expression/beyond_dart_semantics_07.expression.yaml
@@ -46,7 +46,7 @@ type_bounds: []
 type_defaults: []
 method: "foo"
 static: true
-offset: 94
+offset: 108
 scriptUri: main.dart
 expression: |
   list.first[1]
diff --git a/pkg/front_end/testcases/expression/beyond_dart_semantics_07.expression.yaml.expect b/pkg/front_end/testcases/expression/beyond_dart_semantics_07.expression.yaml.expect
index 28ceb3d7d93..5bddb10b62e 100644
--- a/pkg/front_end/testcases/expression/beyond_dart_semantics_07.expression.yaml.expect
+++ b/pkg/front_end/testcases/expression/beyond_dart_semantics_07.expression.yaml.expect
@@ -1,4 +1,4 @@
 Errors: {
 }
-static method /* from org-dartlang-debug:synthetic_debug_expression */ debugExpr(dart.core::_GrowableList<main::A> list) → dynamic
-  return list.{dart.core::_GrowableList::first}{main::A}{dynamic}.[](1);
+static method /* from org-dartlang-debug:synthetic_debug_expression */ debugExpr(dart.core::List<main::A> list) → dynamic
+  return list.{dart.core::Iterable::first}{main::A}{dynamic}.[](1);
diff --git a/pkg/front_end/testcases/expression/beyond_dart_semantics_08.expression.yaml b/pkg/front_end/testcases/expression/beyond_dart_semantics_08.expression.yaml
index 36207f523c3..34f49a723f7 100644
--- a/pkg/front_end/testcases/expression/beyond_dart_semantics_08.expression.yaml
+++ b/pkg/front_end/testcases/expression/beyond_dart_semantics_08.expression.yaml
@@ -46,7 +46,7 @@ type_bounds: []
 type_defaults: []
 method: "foo"
 static: true
-offset: 94
+offset: 108
 scriptUri: main.dart
 expression: |
   list.first[1] = 42
diff --git a/pkg/front_end/testcases/expression/beyond_dart_semantics_08.expression.yaml.expect b/pkg/front_end/testcases/expression/beyond_dart_semantics_08.expression.yaml.expect
index 133eff746c0..ad73151b498 100644
--- a/pkg/front_end/testcases/expression/beyond_dart_semantics_08.expression.yaml.expect
+++ b/pkg/front_end/testcases/expression/beyond_dart_semantics_08.expression.yaml.expect
@@ -1,4 +1,4 @@
 Errors: {
 }
-static method /* from org-dartlang-debug:synthetic_debug_expression */ debugExpr(dart.core::_GrowableList<main::A> list) → dynamic
-  return let final main::A #t1 = list.{dart.core::_GrowableList::first}{main::A} in let final dart.core::int #t2 = 1 in let final dart.core::int #t3 = 42 in let final void #t4 = #t1{dynamic}.[]=(#t2, #t3) in #t3;
+static method /* from org-dartlang-debug:synthetic_debug_expression */ debugExpr(dart.core::List<main::A> list) → dynamic
+  return let final main::A #t1 = list.{dart.core::Iterable::first}{main::A} in let final dart.core::int #t2 = 1 in let final dart.core::int #t3 = 42 in let final void #t4 = #t1{dynamic}.[]=(#t2, #t3) in #t3;
diff --git a/pkg/front_end/testcases/expression/beyond_dart_semantics_09.expression.yaml b/pkg/front_end/testcases/expression/beyond_dart_semantics_09.expression.yaml
index 274b35cb47c..643b83b886c 100644
--- a/pkg/front_end/testcases/expression/beyond_dart_semantics_09.expression.yaml
+++ b/pkg/front_end/testcases/expression/beyond_dart_semantics_09.expression.yaml
@@ -46,7 +46,7 @@ type_bounds: []
 type_defaults: []
 method: "foo"
 static: true
-offset: 94
+offset: 108
 scriptUri: main.dart
 expression: |
   -list.first
diff --git a/pkg/front_end/testcases/expression/beyond_dart_semantics_09.expression.yaml.expect b/pkg/front_end/testcases/expression/beyond_dart_semantics_09.expression.yaml.expect
index 6c4e44c26e7..0041ab983d0 100644
--- a/pkg/front_end/testcases/expression/beyond_dart_semantics_09.expression.yaml.expect
+++ b/pkg/front_end/testcases/expression/beyond_dart_semantics_09.expression.yaml.expect
@@ -1,4 +1,4 @@
 Errors: {
 }
-static method /* from org-dartlang-debug:synthetic_debug_expression */ debugExpr(dart.core::_GrowableList<main::A> list) → dynamic
-  return list.{dart.core::_GrowableList::first}{main::A}{dynamic}.unary-();
+static method /* from org-dartlang-debug:synthetic_debug_expression */ debugExpr(dart.core::List<main::A> list) → dynamic
+  return list.{dart.core::Iterable::first}{main::A}{dynamic}.unary-();
diff --git a/pkg/front_end/testcases/expression/beyond_dart_semantics_10.expression.yaml b/pkg/front_end/testcases/expression/beyond_dart_semantics_10.expression.yaml
index 6f4f2093b3b..10af5d06e7a 100644
--- a/pkg/front_end/testcases/expression/beyond_dart_semantics_10.expression.yaml
+++ b/pkg/front_end/testcases/expression/beyond_dart_semantics_10.expression.yaml
@@ -46,7 +46,7 @@ type_bounds: []
 type_defaults: []
 method: "foo"
 static: true
-offset: 94
+offset: 108
 scriptUri: main.dart
 expression: |
   list.first + 2
diff --git a/pkg/front_end/testcases/expression/beyond_dart_semantics_10.expression.yaml.expect b/pkg/front_end/testcases/expression/beyond_dart_semantics_10.expression.yaml.expect
index 3a0e2d67dc2..f8ef199f3ff 100644
--- a/pkg/front_end/testcases/expression/beyond_dart_semantics_10.expression.yaml.expect
+++ b/pkg/front_end/testcases/expression/beyond_dart_semantics_10.expression.yaml.expect
@@ -1,4 +1,4 @@
 Errors: {
 }
-static method /* from org-dartlang-debug:synthetic_debug_expression */ debugExpr(dart.core::_GrowableList<main::A> list) → dynamic
-  return list.{dart.core::_GrowableList::first}{main::A}{dynamic}.+(2);
+static method /* from org-dartlang-debug:synthetic_debug_expression */ debugExpr(dart.core::List<main::A> list) → dynamic
+  return list.{dart.core::Iterable::first}{main::A}{dynamic}.+(2);