cc: Split Proxy to eliminate unnecessary dependencies on the impl side

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/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_