cc: Make separate interface for BeginFrame ipc from OutputSurface

content/renderer/gpu/compositor_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 CONTENT_RENDERER_GPU_COMPOSITOR_EXTERNAL_BEGIN_FRAME_SOURCE_H_
+#define CONTENT_RENDERER_GPU_COMPOSITOR_EXTERNAL_BEGIN_FRAME_SOURCE_H_
+
+#include "base/basictypes.h"
+#include "base/compiler_specific.h"
+#include "base/memory/ref_counted.h"
+#include "cc/scheduler/begin_frame_source.h"
+
+namespace IPC {
+class ForwardingMessageFilter;
+class Message;
+class SyncMessageFilter;
+}
+
+namespace content {
+
+// This class can be created only on the main thread, but then becomes pinned
+// to a fixed thread where cc::Scheduler is running.
+class CompositorExternalBeginFrameSource : public cc::ExternalBeginFrameSource {
+ public:
+  explicit CompositorExternalBeginFrameSource(int routing_id);
+
+  // cc::ExternalBeginFrameSource implementation.
+  virtual void OnNeedsBeginFramesChange(bool needs_begin_frames) override;
+  virtual void SetClientReady() override;
+
+ private:
+  class CompositorExternalBeginFrameSourceProxy
+      : public base::RefCountedThreadSafe<
+                   CompositorExternalBeginFrameSourceProxy> {
+   public:
+    explicit CompositorExternalBeginFrameSourceProxy(
+        CompositorExternalBeginFrameSource* begin_frame_source)
+        : begin_frame_source_(begin_frame_source) {}
+    void ClearBeginFrameSource() { begin_frame_source_ = NULL; }
+    void OnMessageReceived(const IPC::Message& message) {
+      if (begin_frame_source_)
+        begin_frame_source_->OnMessageReceived(message);
+    }
+
+   private:
+    friend class base::RefCountedThreadSafe<
+                     CompositorExternalBeginFrameSourceProxy>;
+    virtual ~CompositorExternalBeginFrameSourceProxy() {}
+
+    CompositorExternalBeginFrameSource* begin_frame_source_;
+
+    DISALLOW_COPY_AND_ASSIGN(CompositorExternalBeginFrameSourceProxy);
+  };
+
+  virtual ~CompositorExternalBeginFrameSource();
+
+  void OnMessageReceived(const IPC::Message& message);
+
+  void OnBeginFrame(const cc::BeginFrameArgs& args);
+  bool Send(IPC::Message* message);
+
+  scoped_refptr<IPC::ForwardingMessageFilter> begin_frame_source_filter_;
+  scoped_refptr<CompositorExternalBeginFrameSourceProxy>
+      begin_frame_source_proxy_;
+  scoped_refptr<IPC::SyncMessageFilter> message_sender_;
+  int routing_id_;
+
+  DISALLOW_COPY_AND_ASSIGN(CompositorExternalBeginFrameSource);
+};
+
+}  // namespace content
+
+#endif  // CONTENT_RENDERER_GPU_COMPOSITOR_EXTERNAL_BEGIN_FRAME_SOURCE_H_