Faster invocation of custom comparator function.

src/runtime.cc

Index: src/runtime.cc
diff --git a/src/runtime.cc b/src/runtime.cc
index 9199290a9113db7404884d7d5e3d950de0ecf7aa..ae04ce3f380c883b31eb1a03dfaecf90c84852f3 100644
--- a/src/runtime.cc
+++ b/src/runtime.cc
@@ -1363,6 +1363,13 @@ static Object* Runtime_SpecialArrayFunctions(Arguments args) {
 }
 
 
+static Object* Runtime_GetGlobalReceiver(Arguments args) {
+  // Returns a real global receiver, not one of builtins object.
+  Context* global_context = Top::context()->global()->global_context();
+  return global_context->global()->global_receiver();
+}
+
+
 static Object* Runtime_MaterializeRegExpLiteral(Arguments args) {
   HandleScope scope;
   ASSERT(args.length() == 4);