Add a cctest for using a C++ FunctionCallback as an Object.observe observer

test/cctest/test-object-observe.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 744 matching lines @@
                             notifier);
     CompileRun("var obj2 = {};"
                "var notifier2 = Object.getNotifier(obj2);"
                "notifier2.performChange.call("
                    "notifier, 'foo', function(){})");
   }
 
   CcTest::isolate()->ContextDisposedNotification();
   CheckSurvivingGlobalObjectsCount(1);
 }
+
+
+static void ObserverCallback(const FunctionCallbackInfo<Value>& args) {
+  *static_cast<int*>(Handle<External>::Cast(args.Data())->Value()) =
+      Handle<Array>::Cast(args[0])->Length();
+}
+
+
+TEST(ObjectObserveCallsCppFunction) {
+  Isolate* isolate = CcTest::isolate();
+  HandleScope scope(isolate);
+  LocalContext context(isolate);
+  int numRecordsSent = 0;
+  Handle<Function> observer =
+      Function::New(CcTest::isolate(), ObserverCallback,
+                    External::New(isolate, &numRecordsSent));
+  context->Global()->Set(String::NewFromUtf8(CcTest::isolate(), "observer"),
+                         observer);
+  CompileRun(
+      "var obj = {};"
+      "Object.observe(obj, observer);"
+      "obj.foo = 1;"
+      "obj.bar = 2;");
+  CHECK_EQ(2, numRecordsSent);
+}
+
+
+TEST(ObjectObserveCallsFunctionTemplateInstance) {
+  Isolate* isolate = CcTest::isolate();
+  HandleScope scope(isolate);
+  LocalContext context(isolate);
+  int numRecordsSent = 0;
+  Handle<FunctionTemplate> tmpl = FunctionTemplate::New(
+      isolate, ObserverCallback, External::New(isolate, &numRecordsSent));
+  context->Global()->Set(String::NewFromUtf8(CcTest::isolate(), "observer"),
+                         tmpl->GetFunction());
+  CompileRun(
+      "var obj = {};"
+      "Object.observe(obj, observer);"
+      "obj.foo = 1;"
+      "obj.bar = 2;");
+  CHECK_EQ(2, numRecordsSent);
+}