implement LabeledStatement and Break in kernel

pkg/compiler/lib/src/ssa/nodes.dart

 // Copyright (c) 2012, 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.
 
 import '../closure.dart';
 import '../common.dart';
 import '../common/backend_api.dart' show BackendClasses;
 import '../compiler.dart' show Compiler;
 import '../constants/constant_system.dart';
 import '../constants/values.dart';
@@ skipping 2143 matching lines @@
   HJump(this.target)
       : label = null,
         super(const <HInstruction>[]);
   HJump.toLabel(LabelDefinition label)
       : label = label,
         target = label.target,
         super(const <HInstruction>[]);
 }
 
 class HBreak extends HJump {
-  /**
-   * Signals that this is a special break instruction for the synthetic loop
-   * generatedfor a switch statement with continue statements. See
-   * [SsaFromAstMixin.buildComplexSwitchStatement] for detail.
-   */
+  /// Signals that this is a special break instruction for the synthetic loop
+  /// generated for a switch statement with continue statements. See
+  /// [SsaFromAstMixin.buildComplexSwitchStatement] for detail.
   final bool breakSwitchContinueLoop;
   HBreak(JumpTarget target, {bool this.breakSwitchContinueLoop: false})
       : super(target);
   HBreak.toLabel(LabelDefinition label)
       : breakSwitchContinueLoop = false,
         super.toLabel(label);
   toString() => (label != null) ? 'break ${label.labelName}' : 'break';
   accept(HVisitor visitor) => visitor.visitBreak(this);
 }
 
@@ skipping 1268 matching lines @@
 class HDynamicType extends HRuntimeType {
   HDynamicType(DynamicType dartType, TypeMask instructionType)
       : super(const <HInstruction>[], dartType, instructionType);
 
   accept(HVisitor visitor) => visitor.visitDynamicType(this);
 
   int typeCode() => HInstruction.DYNAMIC_TYPE_TYPECODE;
 
   bool typeEquals(HInstruction other) => other is HDynamicType;
 }