dart2js cps: Some fixes for yield.

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

Index: pkg/compiler/lib/src/tree_ir/tree_ir_tracer.dart
diff --git a/pkg/compiler/lib/src/tree_ir/tree_ir_tracer.dart b/pkg/compiler/lib/src/tree_ir/tree_ir_tracer.dart
index b310650a199ef9228614544c8bbeda1e72a4319d..68299e3af68de28f72558c42d574c198a3fd3987 100644
--- a/pkg/compiler/lib/src/tree_ir/tree_ir_tracer.dart
+++ b/pkg/compiler/lib/src/tree_ir/tree_ir_tracer.dart
@@ -179,9 +179,9 @@ class BlockCollector extends StatementVisitor {
     _addStatement(node);
   }
 
-  @override
   visitYield(Yield node) {
     _addStatement(node);
+    visitStatement(node.next);
   }
 }
 
@@ -344,7 +344,8 @@ class TreeTracer extends TracerUtil with StatementVisitor {
 
   @override
   visitYield(Yield node) {
-    printStatement(null, 'yield ${expr(node.input)}');
+    String name = node.hasStar ? 'yield*' : 'yield';
+    printStatement(null, '$name ${expr(node.input)}');
   }
 }