[dart2js] Tag all sources with @dart = 2.10

Change-Id: Ie9c7548dc81b58db0c1149124db79e4cf1430cc1
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/239723
Reviewed-by: Nate Biggs <natebiggs@google.com>
Reviewed-by: Joshua Litt <joshualitt@google.com>
Commit-Queue: Stephen Adams <sra@google.com>

pkg/compiler/bin/dart2js.dart

@@ -2,6 +2,8 @@
 // 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.
 
+// @dart = 2.10
+
 /// Entrypoint to run the compiler. This entrypoint is currently only used by
 /// dart2js developers. To run the compiler you now can:
 ///   * call `pub get` in the pkg/compiler folder.

pkg/compiler/lib/compiler.dart

@@ -2,6 +2,8 @@
 // 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.
 
+// @dart = 2.10
+
 library compiler;
 
 import 'dart:async';

pkg/compiler/lib/src/closure.dart

@@ -2,6 +2,8 @@
 // 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.
 
+// @dart = 2.10
+
 import 'package:kernel/ast.dart' as ir;
 import 'common.dart';
 import 'elements/entities.dart';

pkg/compiler/lib/src/colors.dart

@@ -2,6 +2,8 @@
 // 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.
 
+// @dart = 2.10
+
 library dart2js.colors;
 
 // See http://en.wikipedia.org/wiki/ANSI_escape_code#CSI_codes

pkg/compiler/lib/src/common.dart

@@ -2,6 +2,8 @@
 // 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.
 
+// @dart = 2.10
+
 /// Library that re-exports libraries used throughout the compiler regardless
 /// of phase or subfunctionality.
 library dart2js.common;

pkg/compiler/lib/src/common/codegen.dart

@@ -2,6 +2,8 @@
 // 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.
 
+// @dart = 2.10
+
 library dart2js.common.codegen;
 
 import 'package:js_ast/src/precedence.dart' as js show PRIMARY;

pkg/compiler/lib/src/common/elements.dart

@@ -2,6 +2,8 @@
 // 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.
 
+// @dart = 2.10
+
 import '../common.dart';
 import '../constants/constant_system.dart' as constant_system;
 import '../constants/values.dart';

pkg/compiler/lib/src/common/metrics.dart

@@ -2,6 +2,8 @@
 // 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.
 
+// @dart = 2.10
+
 library dart2js.common.metrics;
 
 /// A collection of metrics that is normally associated with a task.

pkg/compiler/lib/src/common/names.dart

@@ -2,6 +2,8 @@
 // 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.
 
+// @dart = 2.10
+
 /// Library containing identifier, names, and selectors commonly used through
 /// the compiler.
 library dart2js.common.names;

pkg/compiler/lib/src/common/tasks.dart

@@ -2,6 +2,8 @@
 // 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.
 
+// @dart = 2.10
+
 library dart2js.common.tasks;
 
 import 'dart:async'

pkg/compiler/lib/src/common/work.dart

@@ -2,6 +2,8 @@
 // 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.
 
+// @dart = 2.10
+
 library dart2js.common.work;
 
 import '../elements/entities.dart' show MemberEntity;

pkg/compiler/lib/src/compiler.dart

@@ -2,6 +2,8 @@
 // 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.
 
+// @dart = 2.10
+
 library dart2js.compiler_base;
 
 import 'dart:async' show Future;

pkg/compiler/lib/src/constants/constant_system.dart

@@ -2,6 +2,8 @@
 // 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.
 
+// @dart = 2.10
+
 /// Constant system following the semantics for Dart code that has been
 /// compiled to JavaScript.
 library dart2js.constant_system;

pkg/compiler/lib/src/constants/values.dart

@@ -2,6 +2,8 @@
 // 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.
 
+// @dart = 2.10
+
 library dart2js.constants.values;
 
 import '../common.dart';

pkg/compiler/lib/src/dart2js.dart

@@ -2,6 +2,8 @@
 // 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.
 
+// @dart = 2.10
+
 library dart2js.cmdline;
 
 import 'dart:async' show Future;

pkg/compiler/lib/src/deferred_load/algorithm_state.dart

@@ -2,6 +2,8 @@
 // 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.
 
+// @dart = 2.10
+
 import 'entity_data.dart';
 import 'entity_data_info.dart';
 import 'import_set.dart';

pkg/compiler/lib/src/deferred_load/deferred_load.dart

@@ -2,6 +2,8 @@
 // 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.
 
+// @dart = 2.10
+
 /// *Overview of deferred loading*
 ///
 /// Deferred loading allows developers to specify deferred imports. These

pkg/compiler/lib/src/deferred_load/entity_data.dart

@@ -2,6 +2,8 @@
 // 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.
 
+// @dart = 2.10
+
 import '../constants/values.dart' show ConstantValue;
 import '../elements/entities.dart';
 

pkg/compiler/lib/src/deferred_load/entity_data_info.dart

@@ -2,6 +2,8 @@
 // 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.
 
+// @dart = 2.10
+
 import 'package:kernel/ast.dart' as ir;
 import 'package:kernel/type_environment.dart' as ir;
 

pkg/compiler/lib/src/deferred_load/import_set.dart

@@ -2,6 +2,8 @@
 // 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.
 
+// @dart = 2.10
+
 import 'output_unit.dart';
 
 import 'program_split_constraints/builder.dart' as psc show SetTransition;

pkg/compiler/lib/src/deferred_load/output_unit.dart

@@ -2,6 +2,8 @@
 // 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.
 
+// @dart = 2.10
+
 import 'package:front_end/src/api_unstable/dart2js.dart' as fe;
 
 import '../common.dart';

pkg/compiler/lib/src/deferred_load/program_split_constraints/builder.dart

@@ -2,6 +2,8 @@
 // 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.
 
+// @dart = 2.10
+
 import 'dart:collection';
 
 import 'nodes.dart';

pkg/compiler/lib/src/deferred_load/program_split_constraints/nodes.dart

@@ -2,6 +2,8 @@
 // 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.
 
+// @dart = 2.10
+
 /// A [Node] is an abstract base class for all [Node]s parsed from json
 /// constraints.
 abstract class Node {

pkg/compiler/lib/src/deferred_load/program_split_constraints/parser.dart

@@ -2,6 +2,8 @@
 // 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.
 
+// @dart = 2.10
+
 import 'dart:convert';
 
 import 'nodes.dart';

pkg/compiler/lib/src/deferred_load/work_queue.dart

@@ -2,6 +2,8 @@
 // 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.
 
+// @dart = 2.10
+
 import 'dart:collection' show Queue;
 
 import 'algorithm_state.dart';

pkg/compiler/lib/src/diagnostics/diagnostic_listener.dart

@@ -2,6 +2,8 @@
 // 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.
 
+// @dart = 2.10
+
 library dart2js.diagnostic_listener;
 
 import '../../compiler.dart' as api;

pkg/compiler/lib/src/diagnostics/invariant.dart

@@ -2,6 +2,8 @@
 // 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.
 
+// @dart = 2.10
+
 library dart2js.diagnostics.invariant;
 
 import 'spannable.dart';

pkg/compiler/lib/src/diagnostics/messages.dart

@@ -2,6 +2,8 @@
 // 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.
 
+// @dart = 2.10
+
 /// The messages in this file should follow the [Guide for Writing
 /// Diagnostics](../../../../front_end/lib/src/fasta/diagnostics.md).
 ///

pkg/compiler/lib/src/diagnostics/source_span.dart

@@ -2,6 +2,8 @@
 // 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.
 
+// @dart = 2.10
+
 library dart2js.diagnostics.source_span;
 
 import 'spannable.dart' show Spannable;

pkg/compiler/lib/src/diagnostics/spannable.dart

@@ -2,6 +2,8 @@
 // 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.
 
+// @dart = 2.10
+
 library dart2js.diagnostics.spannable;
 
 /// Tagging interface for classes from which source spans can be generated.

pkg/compiler/lib/src/dump_info.dart

@@ -2,6 +2,8 @@
 // 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.
 
+// @dart = 2.10
+
 library dump_info;
 
 import 'dart:convert'

pkg/compiler/lib/src/elements/entities.dart

@@ -2,6 +2,8 @@
 // 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.
 
+// @dart = 2.10
+
 library entities;
 
 import 'package:front_end/src/api_unstable/dart2js.dart' show AsyncModifier;

pkg/compiler/lib/src/elements/entity_utils.dart

@@ -2,6 +2,8 @@
 // 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.
 
+// @dart = 2.10
+
 library entity_utils;
 
 import 'package:front_end/src/api_unstable/dart2js.dart'

pkg/compiler/lib/src/elements/indexed.dart

@@ -2,6 +2,8 @@
 // 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.
 
+// @dart = 2.10
+
 /// Indexed entity interfaces for modeling elements derived from Kernel IR.
 
 import '../elements/entities.dart';

pkg/compiler/lib/src/elements/jumps.dart

@@ -2,6 +2,8 @@
 // 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.
 
+// @dart = 2.10
+
 library elements.jumps;
 
 import 'entities.dart';

pkg/compiler/lib/src/elements/names.dart

@@ -2,6 +2,8 @@
 // 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.
 
+// @dart = 2.10
+
 library dart2js.elements.names;
 
 import 'package:front_end/src/api_unstable/dart2js.dart' show $_;

pkg/compiler/lib/src/elements/operators.dart

@@ -2,6 +2,8 @@
 // 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.
 
+// @dart = 2.10
+
 library dart2js.operators;
 
 import 'names.dart' show PublicName;

pkg/compiler/lib/src/elements/types.dart

@@ -2,6 +2,8 @@
 // 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.
 
+// @dart = 2.10
+
 import '../common/elements.dart';
 import '../common/names.dart';
 import '../options.dart';

pkg/compiler/lib/src/enqueue.dart

@@ -2,6 +2,8 @@
 // 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.
 
+// @dart = 2.10
+
 library dart2js.enqueue;
 
 import 'common/elements.dart' show ElementEnvironment;

pkg/compiler/lib/src/environment.dart

@@ -2,6 +2,8 @@
 // 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.
 
+// @dart = 2.10
+
 /// Collects definitions provided to the compiler via the `-D` flag.
 ///
 /// Environment variables can be used in the user code in two ways. From

pkg/compiler/lib/src/hash/sha1.dart

@@ -2,6 +2,8 @@
 // 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.
 
+// @dart = 2.10
+
 import 'dart:convert';
 
 import 'package:crypto/crypto.dart';

pkg/compiler/lib/src/inferrer/abstract_value_domain.dart

@@ -2,6 +2,8 @@
 // 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.
 
+// @dart = 2.10
+
 library dart2js.abstract_value_domain;
 
 import '../constants/values.dart' show ConstantValue, PrimitiveConstantValue;

pkg/compiler/lib/src/inferrer/builder_kernel.dart

@@ -2,6 +2,8 @@
 // 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.
 
+// @dart = 2.10
+
 import 'package:kernel/ast.dart' as ir;
 
 import '../closure.dart';

pkg/compiler/lib/src/inferrer/closure_tracer.dart

@@ -2,6 +2,8 @@
 // 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.
 
+// @dart = 2.10
+
 library compiler.src.inferrer.closure_tracer;
 
 import '../common/names.dart' show Identifiers, Names;

pkg/compiler/lib/src/inferrer/debug.dart

@@ -2,6 +2,8 @@
 // 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.
 
+// @dart = 2.10
+
 /// Values used only for debugging type inference.
 library compiler.src.inferrer.debug;
 

pkg/compiler/lib/src/inferrer/inferrer_engine.dart

@@ -2,6 +2,8 @@
 // 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.
 
+// @dart = 2.10
+
 import 'package:kernel/ast.dart' as ir;
 
 import '../../compiler.dart';

pkg/compiler/lib/src/inferrer/list_tracer.dart

@@ -2,6 +2,8 @@
 // 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.
 
+// @dart = 2.10
+
 library compiler.src.inferrer.list_tracer;
 
 import '../common/names.dart';

pkg/compiler/lib/src/inferrer/locals_handler.dart

@@ -2,6 +2,8 @@
 // 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.
 
+// @dart = 2.10
+
 library locals_handler;
 
 import 'dart:collection' show IterableMixin;

pkg/compiler/lib/src/inferrer/map_tracer.dart

@@ -2,6 +2,8 @@
 // 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.
 
+// @dart = 2.10
+
 library compiler.src.inferrer.map_tracer;
 
 import '../common/names.dart';

pkg/compiler/lib/src/inferrer/node_tracer.dart

@@ -2,6 +2,8 @@
 // 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.
 
+// @dart = 2.10
+
 library compiler.src.inferrer.node_tracer;
 
 import '../common/names.dart' show Identifiers;

pkg/compiler/lib/src/inferrer/powersets/powerset_bits.dart

@@ -2,6 +2,8 @@
 // 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.
 
+// @dart = 2.10
+
 import '../../common/elements.dart' show CommonElements;
 import '../../constants/values.dart';
 import '../../elements/entities.dart';

pkg/compiler/lib/src/inferrer/powersets/powersets.dart

@@ -2,6 +2,8 @@
 // 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.
 
+// @dart = 2.10
+
 import '../../constants/values.dart' show ConstantValue, PrimitiveConstantValue;
 import '../../elements/entities.dart';
 import '../../elements/names.dart';

pkg/compiler/lib/src/inferrer/powersets/wrapped.dart

@@ -2,6 +2,8 @@
 // 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.
 
+// @dart = 2.10
+
 import '../../constants/values.dart' show ConstantValue, PrimitiveConstantValue;
 import '../../elements/entities.dart';
 import '../../elements/names.dart';

pkg/compiler/lib/src/inferrer/set_tracer.dart

@@ -2,6 +2,8 @@
 // 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.
 
+// @dart = 2.10
+
 library compiler.src.inferrer.set_tracer;
 
 import '../common/names.dart';

pkg/compiler/lib/src/inferrer/trivial.dart

@@ -2,6 +2,8 @@
 // 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.
 
+// @dart = 2.10
+
 import '../constants/values.dart' show ConstantValue, PrimitiveConstantValue;
 import '../elements/entities.dart';
 import '../elements/names.dart';

pkg/compiler/lib/src/inferrer/type_graph_dump.dart

@@ -1,6 +1,9 @@
 // Copyright (c) 2016, 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.
+
+// @dart = 2.10
+
 library dart2js.inferrer.type_graph_dump;
 
 import '../../compiler.dart';

pkg/compiler/lib/src/inferrer/type_graph_inferrer.dart

@@ -2,6 +2,8 @@
 // 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.
 
+// @dart = 2.10
+
 library type_graph_inferrer;
 
 import 'dart:collection' show Queue;

pkg/compiler/lib/src/inferrer/type_graph_nodes.dart

@@ -2,6 +2,8 @@
 // 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.
 
+// @dart = 2.10
+
 library compiler.src.inferrer.type_graph_nodes;
 
 import 'dart:collection' show IterableBase;

pkg/compiler/lib/src/inferrer/type_system.dart

@@ -2,6 +2,8 @@
 // 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.
 
+// @dart = 2.10
+
 import 'package:kernel/ast.dart' as ir;
 import '../common.dart';
 import '../constants/values.dart' show BoolConstantValue;

pkg/compiler/lib/src/inferrer/typemasks/constants.dart

@@ -2,6 +2,8 @@
 // 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.
 
+// @dart = 2.10
+
 library types.constants;
 
 import '../../constants/constant_system.dart' as constant_system;

pkg/compiler/lib/src/inferrer/typemasks/container_type_mask.dart

@@ -2,6 +2,8 @@
 // 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.
 
+// @dart = 2.10
+
 part of masks;
 
 /// A [TypeMask] for a specific allocation site of a container (currently only

pkg/compiler/lib/src/inferrer/typemasks/dictionary_type_mask.dart

@@ -2,6 +2,8 @@
 // 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.
 
+// @dart = 2.10
+
 part of masks;
 
 /// A [DictionaryTypeMask] is a [TypeMask] for a specific allocation

pkg/compiler/lib/src/inferrer/typemasks/flat_type_mask.dart

@@ -2,6 +2,8 @@
 // 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.
 
+// @dart = 2.10
+
 part of masks;
 
 enum _FlatTypeMaskKind { empty, exact, subclass, subtype }

pkg/compiler/lib/src/inferrer/typemasks/forwarding_type_mask.dart

@@ -2,6 +2,8 @@
 // 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.
 
+// @dart = 2.10
+
 part of masks;
 
 /// A type mask that wraps another one, and delegates all its

pkg/compiler/lib/src/inferrer/typemasks/map_type_mask.dart

@@ -2,6 +2,8 @@
 // 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.
 
+// @dart = 2.10
+
 part of masks;
 
 /// A [MapTypeMask] is a [TypeMask] for a specific allocation

pkg/compiler/lib/src/inferrer/typemasks/masks.dart

@@ -2,6 +2,8 @@
 // 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.
 
+// @dart = 2.10
+
 library masks;
 
 import 'package:kernel/ast.dart' as ir;

pkg/compiler/lib/src/inferrer/typemasks/set_type_mask.dart

@@ -2,6 +2,8 @@
 // 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.
 
+// @dart = 2.10
+
 part of masks;
 
 /// A [SetTypeMask] is a [TypeMask] for a specific allocation site of a set

pkg/compiler/lib/src/inferrer/typemasks/type_mask.dart

@@ -2,6 +2,8 @@
 // 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.
 
+// @dart = 2.10
+
 part of masks;
 
 /// An implementation of a [UniverseSelectorConstraints] that is consists if an

pkg/compiler/lib/src/inferrer/typemasks/union_type_mask.dart

@@ -2,6 +2,8 @@
 // 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.
 
+// @dart = 2.10
+
 part of masks;
 
 class UnionTypeMask extends TypeMask {

pkg/compiler/lib/src/inferrer/typemasks/value_type_mask.dart

@@ -2,6 +2,8 @@
 // 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.
 
+// @dart = 2.10
+
 part of masks;
 
 class ValueTypeMask extends ForwardingTypeMask {

pkg/compiler/lib/src/inferrer/types.dart

@@ -2,6 +2,8 @@
 // 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.
 
+// @dart = 2.10
+
 library types;
 
 import 'package:kernel/ast.dart' as ir;

pkg/compiler/lib/src/io/code_output.dart

@@ -2,6 +2,8 @@
 // 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.
 
+// @dart = 2.10
+
 library dart2js.code_output;
 
 import '../../compiler.dart';

pkg/compiler/lib/src/io/kernel_source_information.dart

@@ -2,6 +2,8 @@
 // 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.
 
+// @dart = 2.10
+
 /// Source information system mapping that attempts a semantic mapping between
 /// offsets of JavaScript code points to offsets of Dart code points.
 

pkg/compiler/lib/src/io/location_provider.dart

@@ -2,6 +2,8 @@
 // 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.
 
+// @dart = 2.10
+
 library dart2js.io.location_provider;
 
 import 'code_output.dart' show CodeOutputListener;

pkg/compiler/lib/src/io/position_information.dart

@@ -2,6 +2,8 @@
 // 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.
 
+// @dart = 2.10
+
 /// Source information system mapping that attempts a semantic mapping between
 /// offsets of JavaScript code points to offsets of Dart code points.
 

pkg/compiler/lib/src/io/source_file.dart

@@ -2,6 +2,8 @@
 // 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.
 
+// @dart = 2.10
+
 library dart2js.io.source_file;
 
 import 'dart:convert' show utf8;

pkg/compiler/lib/src/io/source_information.dart

@@ -2,6 +2,8 @@
 // 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.
 
+// @dart = 2.10
+
 library dart2js.source_information;
 
 import 'package:kernel/ast.dart' as ir;

pkg/compiler/lib/src/io/source_map_builder.dart

@@ -2,6 +2,8 @@
 // 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.
 
+// @dart = 2.10
+
 library dart2js.source_map_builder;
 
 import 'package:front_end/src/api_unstable/dart2js.dart' as fe;

pkg/compiler/lib/src/ir/annotations.dart

@@ -2,6 +2,8 @@
 // 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.
 
+// @dart = 2.10
+
 import 'package:kernel/ast.dart' as ir;
 import 'package:kernel/type_environment.dart' as ir;
 import '../common/names.dart';

pkg/compiler/lib/src/ir/cached_static_type.dart

@@ -2,6 +2,8 @@
 // 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.
 
+// @dart = 2.10
+
 import 'package:kernel/ast.dart' as ir;
 import 'package:kernel/type_environment.dart' as ir;
 import 'static_type_base.dart';

pkg/compiler/lib/src/ir/closure.dart

@@ -2,6 +2,8 @@
 // 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.
 
+// @dart = 2.10
+
 import 'package:kernel/ast.dart' as ir;
 import 'package:kernel/src/printer.dart' as ir;
 import 'package:kernel/text/ast_to_text.dart' as ir show debugNodeToString;

pkg/compiler/lib/src/ir/constants.dart

@@ -2,6 +2,8 @@
 // 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.
 
+// @dart = 2.10
+
 import 'package:front_end/src/api_prototype/constant_evaluator.dart' as ir;
 import 'package:front_end/src/api_unstable/dart2js.dart' as ir;
 import 'package:kernel/ast.dart' as ir;

pkg/compiler/lib/src/ir/element_map.dart

@@ -2,6 +2,8 @@
 // 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.
 
+// @dart = 2.10
+
 import 'package:kernel/ast.dart' as ir;
 import 'package:kernel/core_types.dart' as ir;
 

pkg/compiler/lib/src/ir/impact.dart

@@ -2,6 +2,8 @@
 // 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.
 
+// @dart = 2.10
+
 import 'package:kernel/ast.dart' as ir;
 import 'package:kernel/type_environment.dart' as ir;
 

pkg/compiler/lib/src/ir/impact_data.dart

@@ -2,6 +2,8 @@
 // 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.
 
+// @dart = 2.10
+
 import 'package:kernel/ast.dart' as ir;
 import 'package:kernel/class_hierarchy.dart' as ir;
 import 'package:kernel/type_environment.dart' as ir;

pkg/compiler/lib/src/ir/modular.dart

@@ -2,6 +2,8 @@
 // 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.
 
+// @dart = 2.10
+
 import 'package:kernel/ast.dart' as ir;
 import 'package:kernel/class_hierarchy.dart' as ir;
 import 'package:kernel/type_environment.dart' as ir;

pkg/compiler/lib/src/ir/runtime_type_analysis.dart

@@ -2,6 +2,8 @@
 // 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.
 
+// @dart = 2.10
+
 import 'package:kernel/ast.dart' as ir;
 
 import '../common/names.dart';

pkg/compiler/lib/src/ir/scope.dart

@@ -2,6 +2,8 @@
 // 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.
 
+// @dart = 2.10
+
 import 'package:kernel/ast.dart' as ir;
 import 'closure.dart';
 import 'scope_visitor.dart';

pkg/compiler/lib/src/ir/scope_visitor.dart

@@ -2,6 +2,8 @@
 // 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.
 
+// @dart = 2.10
+
 import 'package:kernel/ast.dart' as ir;
 import 'package:kernel/core_types.dart' as ir;
 import 'package:kernel/type_environment.dart' as ir;

pkg/compiler/lib/src/ir/static_type.dart

@@ -2,6 +2,8 @@
 // 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.
 
+// @dart = 2.10
+
 import 'package:front_end/src/api_unstable/dart2js.dart'
     show operatorFromString;
 import 'package:kernel/ast.dart' as ir;

pkg/compiler/lib/src/ir/static_type_base.dart

@@ -2,6 +2,8 @@
 // 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.
 
+// @dart = 2.10
+
 import 'package:kernel/ast.dart' as ir;
 import 'package:kernel/type_environment.dart' as ir;
 

pkg/compiler/lib/src/ir/static_type_cache.dart

@@ -2,6 +2,8 @@
 // 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.
 
+// @dart = 2.10
+
 import 'package:kernel/ast.dart' as ir;
 
 import '../serialization/serialization.dart';

pkg/compiler/lib/src/ir/static_type_provider.dart

@@ -2,6 +2,8 @@
 // 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.
 
+// @dart = 2.10
+
 import 'package:kernel/ast.dart' as ir;
 
 /// Interface for accessing static types on expressions.

pkg/compiler/lib/src/ir/types.dart

@@ -2,6 +2,8 @@
 // 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.
 
+// @dart = 2.10
+
 import '../common/elements.dart';
 import '../elements/entities.dart';
 import '../elements/types.dart';

pkg/compiler/lib/src/ir/util.dart

@@ -2,6 +2,8 @@
 // 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.
 
+// @dart = 2.10
+
 import 'package:kernel/ast.dart' as ir;
 
 import '../common.dart';

pkg/compiler/lib/src/ir/visitors.dart

@@ -2,6 +2,8 @@
 // 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.
 
+// @dart = 2.10
+
 import 'package:kernel/ast.dart' as ir;
 
 import '../constants/constant_system.dart' as constant_system;

pkg/compiler/lib/src/js/js.dart

@@ -2,6 +2,8 @@
 // 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.
 
+// @dart = 2.10
+
 library js;
 
 import 'package:js_ast/js_ast.dart';

pkg/compiler/lib/src/js/js_debug.dart

@@ -2,6 +2,8 @@
 // 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.
 
+// @dart = 2.10
+
 /// Helper for debug JS nodes.
 
 library js.debug;

pkg/compiler/lib/src/js/js_source_mapping.dart

@@ -2,6 +2,8 @@
 // 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.
 
+// @dart = 2.10
+
 library js.source_mapping;
 
 import '../io/code_output.dart'

pkg/compiler/lib/src/js/placeholder_safety.dart

@@ -2,6 +2,8 @@
 // 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.
 
+// @dart = 2.10
+
 library js.safety;
 
 import "js.dart" as js;