Fix labeled break statements.

pkg/compiler/lib/src/kernel/kernel_visitor.dart

 // 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.md file.
 
 import 'package:kernel/ast.dart' as ir;
 import 'package:kernel/frontend/accessors.dart'
     show
         Accessor,
         IndexAccessor,
         NullAwarePropertyAccessor,
@@ skipping 391 matching lines @@
 
   ir.Statement buildBreakTarget(
       ir.Statement statement, Node node, JumpTarget jumpTarget) {
     assert(node.isValidBreakTarget());
     assert(jumpTarget == elements.getTargetDefinition(node));
     associateNode(statement, node);
     if (jumpTarget != null && jumpTarget.isBreakTarget) {
       ir.LabeledStatement breakTarget = getBreakTarget(jumpTarget);
       breakTarget.body = statement;
       statement.parent = breakTarget;
+      print('a target: $statement ${statement.runtimeType}');

[sra1, 2017/01/21 00:17:18]

remove

       return breakTarget;
     } else {
       return statement;
     }
   }
 
   ir.Statement buildContinueTarget(
       ir.Statement statement, Node node, JumpTarget jumpTarget) {
     assert(node.isValidContinueTarget());
     assert(jumpTarget == elements.getTargetDefinition(node));
@@ skipping 680 matching lines @@
     return internalError(node, "TypeVariable");
   }
 
   @override
   ir.Statement visitWhile(While node) {
     ir.Expression condition = visitForValue(node.condition);
     JumpTarget jumpTarget = elements.getTargetDefinition(node);
     ir.Statement body =
         buildContinueTarget(buildStatementInBlock(node.body), node, jumpTarget);
     return buildBreakTarget(
-        associateNode(new ir.WhileStatement(condition, body), node),
+        new ir.WhileStatement(condition, body),
         node,
         jumpTarget);
   }
 
   @override
   ir.YieldStatement visitYield(Yield node) {
     return new ir.YieldStatement(visitForValue(node.expression),
         isYieldStar: node.hasStar);
   }
 
@@ skipping 1736 matching lines @@
       : this(null, true, node, initializers);
 
   accept(ir.Visitor v) => throw "unsupported";
 
   visitChildren(ir.Visitor v) => throw "unsupported";
 
   String toString() {
     return "IrFunction($kind, $isConstructor, $node, $initializers)";
   }
 }