[model] Add missing headers to unit test files in the CFE

Change-Id: I396bbe38dcc4cc65b4758458d6329cf26b31f09d
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/431040
Commit-Queue: Chloe Stefantsova <[email protected]>
Reviewed-by: Johnni Winther <[email protected]>

Author: chloestefantsova

pkg/front_end/testcases/dart2js/async_lowering/collapse_return_await.dart

@@ -1,3 +1,7 @@
+// Copyright (c) 2025, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
 Future<int> bar() {
   return Future.value(123);
 }

pkg/front_end/testcases/dart2js/async_lowering/disabled/basic_return.dart

@@ -1,3 +1,7 @@
+// Copyright (c) 2025, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
 Future<int> foo() async {
   final c = 3;
   return c;

pkg/front_end/testcases/enhanced_enums/issue49429.dart

@@ -1,3 +1,7 @@
+// Copyright (c) 2025, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
 class A {
   const A();
   const factory A.redir() = A;

pkg/front_end/testcases/enhanced_enums/issue49429.dart.strong.expect

@@ -30,7 +30,7 @@ constants  {
 
 Constructor coverage from constants:
 org-dartlang-testcase:///issue49429.dart:
-- A. (from org-dartlang-testcase:///issue49429.dart:2:9)
+- A. (from org-dartlang-testcase:///issue49429.dart:6:9)
 - Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart)
-- E. (from org-dartlang-testcase:///issue49429.dart:9:9)
+- E. (from org-dartlang-testcase:///issue49429.dart:13:9)
 - _Enum. (from org-dartlang-sdk:///sdk/lib/core/enum.dart)

pkg/front_end/testcases/enhanced_enums/issue49429.dart.strong.modular.expect

@@ -30,7 +30,7 @@ constants  {
 
 Constructor coverage from constants:
 org-dartlang-testcase:///issue49429.dart:
-- A. (from org-dartlang-testcase:///issue49429.dart:2:9)
+- A. (from org-dartlang-testcase:///issue49429.dart:6:9)
 - Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart)
-- E. (from org-dartlang-testcase:///issue49429.dart:9:9)
+- E. (from org-dartlang-testcase:///issue49429.dart:13:9)
 - _Enum. (from org-dartlang-sdk:///sdk/lib/core/enum.dart)

pkg/front_end/testcases/enhanced_enums/issue49429.dart.strong.outline.expect

@@ -23,6 +23,6 @@ static method main() → dynamic
 
 
 Extra constant evaluation status:
-Evaluated: ConstructorInvocation @ org-dartlang-testcase:///issue49429.dart:7:3 -> InstanceConstant(const E{_Enum.index: 0, _Enum._name: "element"})
-Evaluated: ListLiteral @ org-dartlang-testcase:///issue49429.dart:6:6 -> ListConstant(const <E>[const E{_Enum.index: 0, _Enum._name: "element"}])
+Evaluated: ConstructorInvocation @ org-dartlang-testcase:///issue49429.dart:11:3 -> InstanceConstant(const E{_Enum.index: 0, _Enum._name: "element"})
+Evaluated: ListLiteral @ org-dartlang-testcase:///issue49429.dart:10:6 -> ListConstant(const <E>[const E{_Enum.index: 0, _Enum._name: "element"}])
 Extra constant evaluation: evaluated: 8, effectively constant: 2

pkg/front_end/testcases/enhanced_enums/issue49429.dart.strong.transformed.expect

@@ -30,7 +30,7 @@ constants  {
 
 Constructor coverage from constants:
 org-dartlang-testcase:///issue49429.dart:
-- A. (from org-dartlang-testcase:///issue49429.dart:2:9)
+- A. (from org-dartlang-testcase:///issue49429.dart:6:9)
 - Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart)
-- E. (from org-dartlang-testcase:///issue49429.dart:9:9)
+- E. (from org-dartlang-testcase:///issue49429.dart:13:9)
 - _Enum. (from org-dartlang-sdk:///sdk/lib/core/enum.dart)

pkg/front_end/testcases/general/bug31124.dart

@@ -1 +1,5 @@
+// Copyright (c) 2025, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
 var a = () => 'b';a();

pkg/front_end/testcases/general/bug31124.dart.strong.expect

@@ -2,15 +2,15 @@ library;
 //
 // Problems in library:
 //
-// pkg/front_end/testcases/general/bug31124.dart:1:22: Error: Expected a function body or '=>'.
+// pkg/front_end/testcases/general/bug31124.dart:5:22: Error: Expected a function body or '=>'.
 // Try adding {}.
 // var a = () => 'b';a();
 //                      ^
 //
-// pkg/front_end/testcases/general/bug31124.dart:1:19: Error: 'a' is already declared in this scope.
+// pkg/front_end/testcases/general/bug31124.dart:5:19: Error: 'a' is already declared in this scope.
 // var a = () => 'b';a();
 //                   ^
-// pkg/front_end/testcases/general/bug31124.dart:1:5: Context: Previous declaration of 'a'.
+// pkg/front_end/testcases/general/bug31124.dart:5:5: Context: Previous declaration of 'a'.
 // var a = () => 'b';a();
 //     ^
 //

pkg/front_end/testcases/general/bug31124.dart.strong.modular.expect

@@ -2,15 +2,15 @@ library;
 //
 // Problems in library:
 //
-// pkg/front_end/testcases/general/bug31124.dart:1:22: Error: Expected a function body or '=>'.
+// pkg/front_end/testcases/general/bug31124.dart:5:22: Error: Expected a function body or '=>'.
 // Try adding {}.
 // var a = () => 'b';a();
 //                      ^
 //
-// pkg/front_end/testcases/general/bug31124.dart:1:19: Error: 'a' is already declared in this scope.
+// pkg/front_end/testcases/general/bug31124.dart:5:19: Error: 'a' is already declared in this scope.
 // var a = () => 'b';a();
 //                   ^
-// pkg/front_end/testcases/general/bug31124.dart:1:5: Context: Previous declaration of 'a'.
+// pkg/front_end/testcases/general/bug31124.dart:5:5: Context: Previous declaration of 'a'.
 // var a = () => 'b';a();
 //     ^
 //