Subrect snapshot support.

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 "content/common/content_export.h"
 #include "ui/gfx/native_widget_types.h"
@@ skipping 76 matching lines @@
   // return 0 if the current context is lost.
   virtual WebKit::WebGLId GenerateCompressedTexture(gfx::Size& size,
                                                     int data_size,
                                                     void* data) = 0;
 
   // Deletes an OpenGL texture.
   virtual void DeleteTexture(WebKit::WebGLId texture_id) = 0;
 
   // Grabs a copy of |texture_id| and saves it into |bitmap|.  No scaling is
   // done.  It is assumed that the texture size matches that of the bitmap.
-  virtual void CopyTextureToBitmap(WebKit::WebGLId texture_id,
+  virtual bool CopyTextureToBitmap(WebKit::WebGLId texture_id,
+                                   gfx::JavaBitmap& bitmap) = 0;
+
+  // Grabs a copy of |texture_id| and saves it into |bitmap|.  No scaling is
+  // done. |src_rect| allows the caller to specify which rect of |texture_id|
+  // to copy to |bitmap|.  It needs to match the size of |bitmap|.  Returns
+  // true if the |texture_id| was copied into |bitmap|, false if not.
+  virtual bool CopyTextureToBitmap(WebKit::WebGLId texture_id,
+                                   const gfx::Rect& src_rect,
                                    gfx::JavaBitmap& bitmap) = 0;
  protected:
   Compositor() {}
 };
 
 }  // namespace content
 
 #endif  // CONTENT_PUBLIC_BROWSER_ANDROID_COMPOSITOR_H_