Elide unnecessary context reload in generated stubs.

src/hydrogen-instructions.h

Index: src/hydrogen-instructions.h
diff --git a/src/hydrogen-instructions.h b/src/hydrogen-instructions.h
index d8f5dec0f7d90b4bc93c9da0da0e604dd0e65050..ee3fd9ba16818b30144d67b18c80425fa7515e73 100644
--- a/src/hydrogen-instructions.h
+++ b/src/hydrogen-instructions.h
@@ -1171,10 +1171,11 @@ class HCompareMap: public HUnaryControlInstruction {
 };
 
 
-class HReturn: public HTemplateControlInstruction<0, 1> {
+class HReturn: public HTemplateControlInstruction<0, 2> {
  public:
-  explicit HReturn(HValue* value) {
+  HReturn(HValue* value, HValue* context) {
     SetOperandAt(0, value);
+    SetOperandAt(1, context);
   }
 
   virtual Representation RequiredInputRepresentation(int index) {
@@ -1184,6 +1185,7 @@ class HReturn: public HTemplateControlInstruction<0, 1> {
   virtual void PrintDataTo(StringStream* stream);
 
   HValue* value() { return OperandAt(0); }
+  HValue* context() { return OperandAt(1); }
 
   DECLARE_CONCRETE_INSTRUCTION(Return)
 };