Support pass-through of stub caller arguments

src/runtime.cc

Index: src/runtime.cc
diff --git a/src/runtime.cc b/src/runtime.cc
index e8003b6731cc77740ed36596a90a59fcfe957027..73cd300c610811927b37d8d9f4964165bb94fc1d 100644
--- a/src/runtime.cc
+++ b/src/runtime.cc
@@ -78,6 +78,9 @@ namespace internal {
   RUNTIME_ASSERT(args[index]->Is##Type());                           \
   Handle<Type> name = args.at<Type>(index);
 
+#define CONVERT_ARG_STUB_CALLER_ARGS(name)                           \
+  Arguments* name = reinterpret_cast<Arguments*>(args[0]);
+
 // Cast the given object to a boolean and store it in a variable with
 // the given name.  If the object is not a boolean call IllegalOperation
 // and return.