cc:: Add remote mode to the compositor

cc/trees/remote_channel_impl.h

Index: cc/trees/remote_channel_impl.h
diff --git a/cc/trees/remote_channel_impl.h b/cc/trees/remote_channel_impl.h
new file mode 100644
index 0000000000000000000000000000000000000000..5d264aef7059d260afcdbc1fa5374870f8809e45
--- /dev/null
+++ b/cc/trees/remote_channel_impl.h
@@ -0,0 +1,136 @@
+// 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_TREES_REMOTE_CHANNEL_IMPL_H_
+#define CC_TREES_REMOTE_CHANNEL_IMPL_H_
+
+#include "base/macros.h"
+#include "base/memory/weak_ptr.h"
+#include "cc/base/cc_export.h"
+#include "cc/base/completion_event.h"
+#include "cc/raster/task_graph_runner.h"
+#include "cc/trees/channel_impl.h"
+#include "cc/trees/proxy_impl.h"
+#include "cc/trees/remote_proto_channel.h"
+
+namespace cc {
+class LayerTreeHost;
+class LayerTreeSettings;
+class RemoteChannelHost;
+
+namespace proto {
+class CompositorMessage;
+class CompositorMessageToImpl;
+class CompositorMessageToMain;
+class InitializeImpl;
+}
+
+class CC_EXPORT RemoteChannelImpl : public ChannelImpl {
+ public:
+  static scoped_ptr<RemoteChannelImpl> Create(
+      RemoteChannelHost* remote_channel_host,
+      TaskGraphRunner* task_graph_runner,
+      const LayerTreeSettings& settings,
+      scoped_refptr<base::SingleThreadTaskRunner> main_task_runner,
+      scoped_refptr<base::SingleThreadTaskRunner> impl_task_runner);
+
+  ~RemoteChannelImpl() override;
+
+  void Initialize();
+
+  void HandleProto(const proto::CompositorMessageToImpl& proto);
+
+  // Should be called on impl thread only.
+  ProxyImpl* GetProxyImplForTesting() const;
+
+ protected:
+  RemoteChannelImpl(
+      RemoteChannelHost* remote_channel_host,
+      TaskGraphRunner* task_graph_runner,
+      const LayerTreeSettings& settings,
+      scoped_refptr<base::SingleThreadTaskRunner> main_task_runner,
+      scoped_refptr<base::SingleThreadTaskRunner> impl_task_runner);
+
+  // virtual for testing.
+  virtual scoped_ptr<ProxyImpl> CreateProxyImpl(
+      ChannelImpl* channel_impl,
+      LayerTreeHost* layer_tree_host,
+      TaskRunnerProvider* task_runner_provider,
+      scoped_ptr<BeginFrameSource> external_begin_frame_source);
+
+  bool MainFrameWillHappenForTesting();
+
+ private:
+  struct MainThreadOnly {
+    RemoteChannelHost* remote_channel_host;
+    scoped_ptr<LayerTreeHost> layer_tree_host;

[David Trainor- moved to gerrit, 2015/12/11 17:13:44]

Comment about the specifics/expectations of this LayerTreeHost here (and why
ownership seems flipped).

[Khushal, 2015/12/11 22:49:37]

Done.

+
+    MainThreadOnly(
+        RemoteChannelImpl* remote_channel_impl,
+        RemoteChannelHost* remote_channel_host,
+        TaskGraphRunner* task_graph_runner,
+        const LayerTreeSettings& settings,
+        scoped_refptr<base::SingleThreadTaskRunner> main_task_runner,
+        scoped_refptr<base::SingleThreadTaskRunner> impl_task_runner);
+    ~MainThreadOnly();
+  };
+
+  struct CompositorThreadOnly {
+    scoped_ptr<ProxyImpl> proxy_impl;
+    scoped_ptr<base::WeakPtrFactory<ProxyImpl>> proxy_impl_weak_factory;
+
+    CompositorThreadOnly();
+    ~CompositorThreadOnly();
+  };
+
+  // Called on impl thread.
+  // ChannelImpl implementation
+  void DidCompleteSwapBuffers() override;
+  void SetRendererCapabilitiesMainCopy(
+      const RendererCapabilities& capabilities) override;
+  void BeginMainFrameNotExpectedSoon() override;
+  void DidCommitAndDrawFrame() override;
+  void SetAnimationEvents(scoped_ptr<AnimationEventsVector> queue) override;
+  void DidLoseOutputSurface() override;
+  void RequestNewOutputSurface() override;
+  void DidInitializeOutputSurface(
+      bool success,
+      const RendererCapabilities& capabilities) override;
+  void DidCompletePageScaleAnimation() override;
+  void PostFrameTimingEventsOnMain(
+      scoped_ptr<FrameTimingTracker::CompositeTimingSet> composite_events,
+      scoped_ptr<FrameTimingTracker::MainFrameTimingSet> main_frame_events)
+      override;
+  void BeginMainFrame(
+      scoped_ptr<BeginMainFrameAndCommitState> begin_main_frame_state) override;
+
+  // Called on impl thread.

[David Trainor- moved to gerrit, 2015/12/11 17:13:44]

Do you need this if you have it above?  I'm fine with it either way, just
pointing it out.

[Khushal, 2015/12/11 22:49:37]

I wasn't sure if having the comment only above the ChannelImpl implementation
makes it clear. But I guess having the "OnImpl" suffix should make it obvious
too.
Removed.

+  void InitializeImplOnImpl(CompletionEvent* completion,
+                            LayerTreeHost* layer_tree_host);
+  void ShutdownImplOnImpl(CompletionEvent* completion);
+
+  // Called on main thread.
+  void MainThreadHasStoppedFlinging();
+
+  MainThreadOnly& main();
+  CompositorThreadOnly& impl();
+  const CompositorThreadOnly& impl() const;
+
+  base::SingleThreadTaskRunner* MainThreadTaskRunner() const;
+  base::SingleThreadTaskRunner* ImplThreadTaskRunner() const;
+
+  // use accessors instead of these variables directly
+  MainThreadOnly main_thread_vars_unsafe_;
+  CompositorThreadOnly compositor_thread_vars_unsafe_;
+
+  TaskRunnerProvider* task_runner_provider_;
+
+  base::WeakPtr<ProxyImpl> proxy_impl_weak_ptr_;
+
+  DISALLOW_COPY_AND_ASSIGN(RemoteChannelImpl);
+};
+
+}  // namespace cc
+
+#endif  // CC_TREES_REMOTE_CHANNEL_IMPL_H_