scheduler: Move the Blink scheduler into Blink

cc/test/fake_impl_task_runner_provider.h

 // 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.
 
 #ifndef CC_TEST_FAKE_IMPL_TASK_RUNNER_PROVIDER_H_
 #define CC_TEST_FAKE_IMPL_TASK_RUNNER_PROVIDER_H_
 
 #include "base/threading/thread_task_runner_handle.h"
 #include "cc/trees/single_thread_proxy.h"
 #include "cc/trees/task_runner_provider.h"
 
-namespace base {
-class SingleThreadIdleTaskRunner;
-}
-
 namespace cc {
 
 class FakeImplTaskRunnerProvider : public TaskRunnerProvider {
  public:
   FakeImplTaskRunnerProvider()
       : TaskRunnerProvider(base::ThreadTaskRunnerHandle::Get(), nullptr),
         set_impl_thread_(this) {}
 
   explicit FakeImplTaskRunnerProvider(
       scoped_refptr<base::SingleThreadTaskRunner> impl_task_runner)
       : TaskRunnerProvider(base::ThreadTaskRunnerHandle::Get(),
                            impl_task_runner),
         set_impl_thread_(this) {}
 
  private:
   DebugScopedSetImplThread set_impl_thread_;
 };
 
 }  // namespace cc
 #endif  // CC_TEST_FAKE_IMPL_TASK_RUNNER_PROVIDER_H_