Optimized TurboFan support for rest args.

src/code-factory.h

Index: src/code-factory.h
diff --git a/src/code-factory.h b/src/code-factory.h
index 8fa17583b9c8e8212368a24b0eb6864c222bfc2e..a4701672d579a3120118c06aa6a879e0132bdf9e 100644
--- a/src/code-factory.h
+++ b/src/code-factory.h
@@ -94,6 +94,7 @@ class CodeFactory final {
 
   static Callable ArgumentsAccess(Isolate* isolate, bool is_unmapped_arguments,
                                   bool has_duplicate_parameters);
+  static Callable RestArgumentsAccess(Isolate* isolate);
 
   static Callable AllocateHeapNumber(Isolate* isolate);
   static Callable AllocateMutableHeapNumber(Isolate* isolate);