Faster invocation of custom comparator function.

src/ia32/virtual-frame-ia32.h

Index: src/ia32/virtual-frame-ia32.h
diff --git a/src/ia32/virtual-frame-ia32.h b/src/ia32/virtual-frame-ia32.h
index 9b6892a51bf2de0dd0818446d8c29ef29df37c77..14fe4662dc2ca69ca80bdd4a790a83ebb5f5c4bd 100644
--- a/src/ia32/virtual-frame-ia32.h
+++ b/src/ia32/virtual-frame-ia32.h
@@ -331,6 +331,10 @@ class VirtualFrame: public ZoneObject {
   // arguments are consumed by the call.
   Result CallStub(CodeStub* stub, Result* arg0, Result* arg1);
 
+  // Call JS function from top of the stack with arguments
+  // taken from the stack.
+  Result CallJSFunction(int arg_count);
+
   // Call runtime given the number of arguments expected on (and
   // removed from) the stack.
   Result CallRuntime(Runtime::Function* f, int arg_count);