dart2js cps: Some fixes for yield.

pkg/compiler/lib/src/tree_ir/tree_ir_tracer.dart

 // Copyright (c) 2014, 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 tree_ir_tracer;
 
 import 'dart:async' show EventSink;
 import '../tracer.dart';
 import 'tree_ir_nodes.dart';
 
@@ skipping 161 matching lines @@
 
   visitExpressionStatement(ExpressionStatement node) {
     _addStatement(node);
     visitStatement(node.next);
   }
 
   visitForeignStatement(ForeignStatement node) {
     _addStatement(node);
   }
 
-  @override
   visitYield(Yield node) {
     _addStatement(node);
+    visitStatement(node.next);
   }
 }
 
 class TreeTracer extends TracerUtil with StatementVisitor {
   String get passName => null;
 
   final EventSink<String> output;
 
   TreeTracer(this.output);
 
@@ skipping 142 matching lines @@
     return e.accept(new SubexpressionVisitor(names));
   }
 
   @override
   visitForeignStatement(ForeignStatement node) {
     printStatement(null, 'foreign ${node.codeTemplate.source}');
   }
 
   @override
   visitYield(Yield node) {
-    printStatement(null, 'yield ${expr(node.input)}');
+    String name = node.hasStar ? 'yield*' : 'yield';
+    printStatement(null, '$name ${expr(node.input)}');
   }
 }
 
 class SubexpressionVisitor extends ExpressionVisitor<String> {
   Names names;
 
   SubexpressionVisitor(this.names);
 
   String visitVariableUse(VariableUse node) {
     return names.varName(node.variable);
@@ skipping 256 matching lines @@
       String prefix = v.element == null ? 'v' : '${v.element.name}_';
       while (name == null || _usedNames.contains(name)) {
         name = "$prefix${_counter++}";
       }
       _names[v] = name;
       _usedNames.add(name);
     }
     return name;
   }
 }