Android Browser Compositor: Add ScheduleComposite() callback.

content/public/browser/android/compositor.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_PUBLIC_BROWSER_ANDROID_COMPOSITOR_H_
 #define CONTENT_PUBLIC_BROWSER_ANDROID_COMPOSITOR_H_
 
 #include "base/callback.h"
 #include "ui/gfx/native_widget_types.h"
 #include "ui/gfx/rect.h"
 #include "ui/gfx/size.h"
 
 namespace WebKit {
 class WebLayer;
 }
 
 namespace content {
 
 // An interface to the browser-side compositor.
 class Compositor {
  public:
+  class Client {
+   public:
+    // Tells the client that it should schedule a composite.
+    virtual void ScheduleComposite() = 0;
+  };
+
   virtual ~Compositor() {}
 
   // Performs the global initialization needed before any compositor
   // instance can be used.
   static void Initialize();
 
   // Creates and returns a compositor instance.
-  static Compositor* Create();
+  static Compositor* Create(Client* client);
 
   // Attaches the layer tree.
   virtual void SetRootLayer(WebKit::WebLayer* root) = 0;
 
   // Set the output surface bounds.
   virtual void SetWindowBounds(const gfx::Size& size) = 0;
 
   // Set the output surface handle which the compositor renders into.
   virtual void SetWindowSurface(ANativeWindow* window) = 0;
 
   // Attempts to composite and read back the result into the provided buffer.
   // The buffer must be at least window width * height * 4 (RGBA) bytes large.
   // The buffer is not modified if false is returned.
   virtual bool CompositeAndReadback(void *pixels, const gfx::Rect& rect) = 0;
 
-  // Callback to be run after the frame has been drawn. It passes back
-  // a synchronization point identifier.
-  typedef base::Callback<void(uint32)> SurfacePresentedCallback;
-
-  virtual void OnSurfaceUpdated(const SurfacePresentedCallback& callback) = 0;
+  // Composite immediately. Used in single-threaded mode.
+  virtual void Composite() = 0;
 
  protected:
   Compositor() {}
 };
 
 }  // namespace content
 
 #endif  // CONTENT_PUBLIC_BROWSER_ANDROID_COMPOSITOR_H_