Very basic Android browser-side compositing support.

content/public/browser/web_contents_delegate.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_WEB_CONTENTS_DELEGATE_H_
 #define CONTENT_PUBLIC_BROWSER_WEB_CONTENTS_DELEGATE_H_
 
 #include <set>
 #include <string>
 
@@ skipping 39 matching lines @@
 
 namespace history {
 class HistoryAddPageArgs;
 }
 
 namespace webkit_glue {
 struct WebIntentData;
 struct WebIntentServiceData;
 }
 
+namespace WebKit {
+class WebLayer;
+}
+
 namespace content {
 
 struct OpenURLParams;
 
 typedef base::Callback< void(const MediaStreamDevices&) > MediaResponseCallback;
 
 // Objects implement this interface to get notified about changes in the
 // WebContents and to provide necessary functionality.
 class CONTENT_EXPORT WebContentsDelegate {
  public:
@@ skipping 230 matching lines @@
   // typically happens when popups are created.
   virtual void WebContentsCreated(WebContents* source_contents,
                                   int64 source_frame_id,
                                   const GURL& target_url,
                                   WebContents* new_contents) {}
 
   // Notifies the delegate that the content restrictions for this tab has
   // changed.
   virtual void ContentRestrictionsChanged(WebContents* source) {}
 
-#if defined(OS_ANDROID)
-  // Returns true if the delegate wants to handle the url instead. Default
-  // returns false.
-  virtual bool ShouldOverrideLoading(const GURL& url);
-#endif
-
   // Notification that the tab is hung.
   virtual void RendererUnresponsive(WebContents* source) {}
 
   // Notification that the tab is no longer hung.
   virtual void RendererResponsive(WebContents* source) {}
 
   // Notification that a worker associated with this tab has crashed.
   virtual void WorkerCrashed(WebContents* source) {}
 
   // Invoked when a main fram navigation occurs.
@@ skipping 95 matching lines @@
   // Asks permission to use the camera and/or microphone. If permission is
   // granted, a call should be made to |callback| with the devices. If the
   // request is denied, a call should be made to |callback| with an empty list
   // of devices. |request| has the details of the request (e.g. which of audio
   // and/or video devices are requested, and lists of available devices).
   virtual void RequestMediaAccessPermission(
       WebContents* web_contents,
       const MediaStreamRequest* request,
       const MediaResponseCallback& callback) {}
 
+#if defined(OS_ANDROID)
+  // Returns true if the delegate wants to handle the url instead. Default
+  // returns false.
+  virtual bool ShouldOverrideLoading(const GURL& url);
+
+  // Called when a compositing layer becomes available for this web contents
+  // so the delegate can add it to the layer tree.
+  virtual void AttachLayer(WebContents* web_contents,
+                           WebKit::WebLayer* layer) {}
+
+  // Called before a compositing layer becomes invalid so the delegate can
+  // remove it from the layer tree.
+  virtual void RemoveLayer(WebContents* web_contents,
+                           WebKit::WebLayer* layer) {}
+#endif
+
  protected:
   virtual ~WebContentsDelegate();
 
  private:
   friend class ::WebContentsImpl;
 
   // Called when |this| becomes the WebContentsDelegate for |source|.
   void Attach(WebContents* source);
 
   // Called when |this| is no longer the WebContentsDelegate for |source|.
   void Detach(WebContents* source);
 
   // The WebContents that this is currently a delegate for.
   std::set<WebContents*> attached_contents_;
 };
 
 }  // namespace content
 
 #endif  // CONTENT_PUBLIC_BROWSER_WEB_CONTENTS_DELEGATE_H_