dart2js: Add support for do/while loops to the CPS backend.

pkg/compiler/lib/src/cps_ir/cps_ir_builder_task.dart

 // Copyright (c) 2013, 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.
 
 library dart2js.ir_builder_task;
 
 import '../closure.dart' as closurelib;
 import '../closure.dart' hide ClosureScope;
 import '../constants/expressions.dart';
 import '../dart_types.dart';
@@ skipping 356 matching lines @@
     if (body is ast.Loop) {
       visit(body);
     } else {
       JumpTarget target = elements.getTargetDefinition(body);
       irBuilder.buildLabeledStatement(
           buildBody: subbuild(body),
           target: target);
     }
   }
 
+  visitDoWhile(ast.DoWhile node) {
+    irBuilder.buildDoWhile(
+        buildBody: subbuild(node.body),
+        buildCondition: subbuild(node.condition),
+        target: elements.getTargetDefinition(node),
+        closureScope: getClosureScopeForNode(node));
+  }
+
   visitWhile(ast.While node) {
     irBuilder.buildWhile(
         buildCondition: subbuild(node.condition),
         buildBody: subbuild(node.body),
         target: elements.getTargetDefinition(node),
         closureScope: getClosureScopeForNode(node));
   }
 
   visitForIn(ast.ForIn node) {
     // [node.declaredIdentifier] can be either an [ast.VariableDefinitions]
@@ skipping 1456 matching lines @@
   SourceInformation buildCall(ast.Node node) {
     return new PositionSourceInformation(
         new TokenSourceLocation(sourceFile, node.getBeginToken(), name));
   }
 
   @override
   SourceInformationBuilder forContext(AstElement element) {
     return new PositionSourceInformationBuilder(element);
   }
 }