Support copying a partial rectangle region from the compositing surface on Aura and GTK.

content/browser/renderer_host/render_widget_host_view_win.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_RENDER_WIDGET_HOST_VIEW_WIN_H_
 #define CONTENT_BROWSER_RENDERER_HOST_RENDER_WIDGET_HOST_VIEW_WIN_H_
 
 #include <atlbase.h>
 #include <atlapp.h>
 #include <atlcrack.h>
@@ skipping 173 matching lines @@
       const gfx::Rect& scroll_rect, int scroll_dx, int scroll_dy,
       const std::vector<gfx::Rect>& copy_rects) OVERRIDE;
   virtual void RenderViewGone(base::TerminationStatus status,
                               int error_code) OVERRIDE;
   // called by WebContentsImpl before DestroyWindow
   virtual void WillWmDestroy() OVERRIDE;
   virtual void Destroy() OVERRIDE;
   virtual void SetTooltipText(const string16& tooltip_text) OVERRIDE;
   virtual BackingStore* AllocBackingStore(const gfx::Size& size) OVERRIDE;
   virtual void CopyFromCompositingSurface(
-      const gfx::Size& size,
+      const gfx::Rect& src_subrect,
+      const gfx::Size& dst_size,
       const base::Callback<void(bool)>& callback,
       skia::PlatformCanvas* output) OVERRIDE;
   virtual void OnAcceleratedCompositingStateChange() OVERRIDE;
   virtual void ProcessTouchAck(WebKit::WebInputEvent::Type type,
                                bool processed) OVERRIDE;
   virtual void SetHasHorizontalScrollbar(
       bool has_horizontal_scrollbar) OVERRIDE;
   virtual void SetScrollOffsetPinning(
       bool is_pinned_to_left, bool is_pinned_to_right) OVERRIDE;
   virtual gfx::GLSurfaceHandle GetCompositingSurface() OVERRIDE;
@@ skipping 345 matching lines @@
   bool touch_events_enabled_;
 
   scoped_ptr<ui::GestureRecognizer> gesture_recognizer_;
 
   DISALLOW_COPY_AND_ASSIGN(RenderWidgetHostViewWin);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_RENDERER_HOST_RENDER_WIDGET_HOST_VIEW_WIN_H_