Two fixes for mojo JS bindings

mojo/bindings/js/support.cc

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "mojo/bindings/js/support.h"
 
 #include "base/bind.h"
 #include "gin/arguments.h"
 #include "gin/converter.h"
 #include "gin/function_template.h"
 #include "gin/object_template_builder.h"
 #include "gin/per_isolate_data.h"
 #include "gin/public/wrapper_info.h"
 #include "gin/wrappable.h"
 #include "mojo/bindings/js/handle.h"
 #include "mojo/bindings/js/waiting_callback.h"
 #include "mojo/public/cpp/environment/default_async_waiter.h"
 #include "mojo/public/cpp/system/core.h"
 
 namespace mojo {
 namespace js {
 
 namespace {
 
 WaitingCallback* AsyncWait(const gin::Arguments& args, mojo::Handle handle,
                            MojoWaitFlags flags,
                            v8::Handle<v8::Function> callback) {
-  gin::Handle<WaitingCallback> waiting_callback =
-      WaitingCallback::Create(args.isolate(), callback);
-
-  MojoAsyncWaiter* waiter = GetDefaultAsyncWaiter();
-  MojoAsyncWaitID wait_id = waiter->AsyncWait(
-      waiter,
-      handle.value(),
-      flags,
-      MOJO_DEADLINE_INDEFINITE,
-      &WaitingCallback::CallOnHandleReady,
-      waiting_callback.get());
-
-  waiting_callback->set_wait_id(wait_id);
-
-  return waiting_callback.get();
+  return WaitingCallback::Create(args.isolate(), callback, handle, flags).get();
 }
 
 void CancelWait(WaitingCallback* waiting_callback) {
-  if (!waiting_callback->wait_id())
-    return;
-
-  MojoAsyncWaiter* waiter = GetDefaultAsyncWaiter();
-  waiter->CancelWait(waiter, waiting_callback->wait_id());
-  waiting_callback->set_wait_id(0);
+  waiting_callback->Cancel();
 }
 
 gin::WrapperInfo g_wrapper_info = { gin::kEmbedderNativeGin };
 
 }  // namespace
 
 const char Support::kModuleName[] = "mojo/public/js/bindings/support";
 
 v8::Local<v8::Value> Support::GetModule(v8::Isolate* isolate) {
   gin::PerIsolateData* data = gin::PerIsolateData::From(isolate);
   v8::Local<v8::ObjectTemplate> templ = data->GetObjectTemplate(
       &g_wrapper_info);
 
   if (templ.IsEmpty()) {
     templ = gin::ObjectTemplateBuilder(isolate)
                 .SetMethod("asyncWait", AsyncWait)
                 .SetMethod("cancelWait", CancelWait)
                 .Build();
 
     data->SetObjectTemplate(&g_wrapper_info, templ);
   }
 
   return templ->NewInstance();
 }
 
 }  // namespace js
 }  // namespace mojo