Introduce CompositorDependencies for RenderWidgetCompositor.

cc/test/fake_external_begin_frame_source.h

+// 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.
+
+#ifndef CC_TEST_FAKE_EXTERNAL_BEGIN_FRAME_SOURCE_H_
+#define CC_TEST_FAKE_EXTERNAL_BEGIN_FRAME_SOURCE_H_
+
+#include "base/memory/weak_ptr.h"
+#include "cc/scheduler/begin_frame_source.h"
+
+namespace cc {
+
+class FakeExternalBeginFrameSource
+    : public BeginFrameSourceMixIn,
+      public NON_EXPORTED_BASE(base::NonThreadSafe) {
+ public:
+  explicit FakeExternalBeginFrameSource(double refresh_rate);
+  virtual ~FakeExternalBeginFrameSource();
+
+  bool is_ready() const { return is_ready_; }
+
+  // BeginFrameSource implementation.
+  void SetClientReady() override;
+
+  // BeginFrameSourceMixIn overrides.
+  void OnNeedsBeginFramesChange(bool needs_begin_frames) override;
+
+  void TestOnBeginFrame();
+
+ private:
+  double milliseconds_per_frame_;
+  bool is_ready_;
+  base::WeakPtrFactory<FakeExternalBeginFrameSource> weak_ptr_factory_;
+};
+
+}  // namespace cc
+
+#endif  // CC_TEST_FAKE_EXTERNAL_BEGIN_FRAME_SOURCE_H_