Fast path for strict closure creation.

src/code-stubs.h

Index: src/code-stubs.h
diff --git a/src/code-stubs.h b/src/code-stubs.h
index 6af45d54faf08f83ad9295f9f35c5ee2816054dc..464d7c0b7737c4db805ada94c930b8e29e0bc4e8 100644
--- a/src/code-stubs.h
+++ b/src/code-stubs.h
@@ -277,12 +277,17 @@ class ToNumberStub: public CodeStub {
 
 class FastNewClosureStub : public CodeStub {
  public:
+  FastNewClosureStub(StrictModeFlag strict_mode)
+    : strict_mode_(strict_mode) { }
+
   void Generate(MacroAssembler* masm);
 
  private:
   const char* GetName() { return "FastNewClosureStub"; }
   Major MajorKey() { return FastNewClosure; }
-  int MinorKey() { return 0; }
+  int MinorKey() { return strict_mode_; }
+
+  StrictModeFlag strict_mode_;
 };