Very basic Android browser-side compositing support.

content/browser/renderer_host/compositor_impl_android.h

+// Copyright (c) 2012 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_BROWSER_RENDERER_HOST_COMPOSITOR_IMPL_ANDROID_H_
+#define CONTENT_BROWSER_RENDERER_HOST_COMPOSITOR_IMPL_ANDROID_H_
+
+#include "base/basictypes.h"
+#include "base/compiler_specific.h"
+#include "base/memory/scoped_ptr.h"
+#include "content/public/browser/android/compositor.h"
+#include "third_party/WebKit/Source/Platform/chromium/public/WebLayer.h"
+#include "third_party/WebKit/Source/Platform/chromium/public/WebLayerTreeView.h"
+#include "third_party/WebKit/Source/Platform/chromium/public/WebLayerTreeViewClient.h"
+
+struct ANativeWindow;
+
+namespace content {
+class GraphicsContext;
+class RenderWidgetHostView;
+
+// -----------------------------------------------------------------------------
+// Browser-side compositor that manages a tree of content and UI layers.
+// -----------------------------------------------------------------------------
+class CompositorImpl : public Compositor,
+                       public WebKit::WebLayerTreeViewClient {
+ public:
+  CompositorImpl();
+  virtual ~CompositorImpl();
+
+  static CompositorImpl* GetInstance();

[klobag.chromium, 2012/08/23 02:08:12]

I agree with Alex. I don't think it is a good idea to have a singleton
Compositor. 

+
+  // Compositor implementation.
+  virtual void SetRootLayer(const WebKit::WebLayer& root) OVERRIDE;
+  virtual void SetWindowSurface(ANativeWindow* window) OVERRIDE;
+  virtual void SetWindowBounds(const gfx::Size& size) OVERRIDE;
+
+  // WebLayerTreeViewClient implementation.
+  virtual void updateAnimations(double frameBeginTime) OVERRIDE;
+  virtual void layout() OVERRIDE;
+  virtual void applyScrollAndScale(const WebKit::WebSize& scrollDelta,
+                                   float scaleFactor) OVERRIDE;
+  virtual WebKit::WebGraphicsContext3D* createContext3D() OVERRIDE;
+  virtual void didRebindGraphicsContext(bool success) OVERRIDE;
+  virtual void didCommit() OVERRIDE;
+  virtual void didCommitAndDrawFrame() OVERRIDE;
+  virtual void didCompleteSwapBuffers() OVERRIDE;
+  virtual void scheduleComposite() OVERRIDE;
+
+  // Callback to be run after the frame has been drawn. It passes back
+  // a synchronization point identifier.
+  typedef base::Callback<void(uint32)> SurfacePresentedCallback;
+
+  void SurfaceUpdated(const SurfacePresentedCallback& callback);
+  void SetCompositorSurface(gfx::GLSurfaceHandle handle) { handle_ = handle; }
+  gfx::Size GetWindowBounds() { return size_; }
+  gfx::GLSurfaceHandle GetCompositorSurface() { return handle_; }
+
+ private:
+  WebKit::WebLayer root_layer_;
+  WebKit::WebLayerTreeView host_;
+
+  scoped_ptr<GraphicsContext> context_;
+
+  gfx::GLSurfaceHandle handle_;
+  gfx::Size size_;
+
+  DISALLOW_COPY_AND_ASSIGN(CompositorImpl);
+};
+
+} // namespace content
+
+#endif  // CONTENT_BROWSER_RENDERER_HOST_COMPOSITOR_IMPL_ANDROID_H_