Add for-of Crankshaft support

src/ast.h

Index: src/ast.h
diff --git a/src/ast.h b/src/ast.h
index f0b140efceaa38e5debe40df0a0ce5e9452a97e2..e27557f3f42c5f789f65d990dfac4510fa291b37 100644
--- a/src/ast.h
+++ b/src/ast.h
@@ -979,9 +979,9 @@ class ForOfStatement: public ForEachStatement {
   }
 
   virtual BailoutId ContinueId() const { return EntryId(); }
-  virtual BailoutId StackCheckId() const { return BackEdgeId(); }
+  virtual BailoutId StackCheckId() const { return BodyId(); }
 
-  BailoutId BackEdgeId() const { return back_edge_id_; }
+  BailoutId BodyId() const { return body_id_; }
 
  protected:
   ForOfStatement(Isolate* isolate, ZoneStringList* labels)
@@ -990,14 +990,14 @@ class ForOfStatement: public ForEachStatement {
         next_result_(NULL),
         result_done_(NULL),
         assign_each_(NULL),
-        back_edge_id_(GetNextId(isolate)) {
+        body_id_(GetNextId(isolate)) {
   }
 
   Expression* assign_iterator_;
   Expression* next_result_;
   Expression* result_done_;
   Expression* assign_each_;
-  const BailoutId back_edge_id_;
+  const BailoutId body_id_;
 };