Schedule bitmap animation timers on the compositor task runner.

third_party/WebKit/Source/platform/scheduler/child/web_scheduler_impl.cc

 // Copyright 2015 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 "platform/scheduler/child/web_scheduler_impl.h"
 
 #include "base/bind.h"
 #include "base/memory/ptr_util.h"
 #include "base/single_thread_task_runner.h"
 #include "platform/scheduler/child/web_task_runner_impl.h"
@@ skipping 52 matching lines @@
 }
 
 blink::WebTaskRunner* WebSchedulerImpl::LoadingTaskRunner() {
   return loading_web_task_runner_.Get();
 }
 
 blink::WebTaskRunner* WebSchedulerImpl::TimerTaskRunner() {
   return timer_web_task_runner_.Get();
 }
 
+blink::WebTaskRunner* WebSchedulerImpl::CompositorTaskRunner() {
+  NOTREACHED();
+  return nullptr;
+}
+
 std::unique_ptr<blink::WebViewScheduler>
 WebSchedulerImpl::CreateWebViewScheduler(
     InterventionReporter*,
     WebViewScheduler::WebViewSchedulerSettings*) {
   NOTREACHED();
   return nullptr;
 }
 
 }  // namespace scheduler
 }  // namespace blink