Plumb the partial swap though image transport.

content/browser/renderer_host/render_widget_host_view.h

 // Copyright (c) 2011 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_H_
 #define CONTENT_BROWSER_RENDERER_HOST_RENDER_WIDGET_HOST_VIEW_H_
 #pragma once
 
 #if defined(OS_MACOSX)
 #include <OpenGL/OpenGL.h>
 #endif
 
 #include <string>
 #include <vector>
 
 #include "base/process_util.h"
 #include "base/callback.h"
 #include "content/common/content_export.h"
 #include "third_party/skia/include/core/SkBitmap.h"
 #include "third_party/skia/include/core/SkColor.h"
 #include "third_party/WebKit/Source/WebKit/chromium/public/WebInputEvent.h"
 #include "third_party/WebKit/Source/WebKit/chromium/public/WebPopupType.h"
 #include "ui/base/ime/text_input_type.h"
 #include "ui/base/range/range.h"
 #include "ui/gfx/native_widget_types.h"
 #include "ui/gfx/rect.h"
 #include "ui/gfx/surface/transport_dib.h"
 
 struct GpuHostMsg_AcceleratedSurfaceBuffersSwapped_Params;
+struct GpuHostMsg_AcceleratedSurfacePostSubBuffer_Params;
 
 class BackingStore;
 class RenderWidgetHost;
 class WebCursor;
 struct NativeWebKeyboardEvent;
 struct ViewHostMsg_AccessibilityNotification_Params;
 
 namespace content {
 class RenderProcessHost;
 }
@@ skipping 150 matching lines @@
   // Called when accelerated compositing state changes.
   virtual void OnAcceleratedCompositingStateChange() = 0;
   // |params.window| and |params.surface_id| indicate which accelerated
   // surface's buffers swapped. |params.renderer_id| and |params.route_id|
   // are used to formulate a reply to the GPU process to prevent it from getting
   // too far ahead. They may all be zero, in which case no flow control is
   // enforced; this case is currently used for accelerated plugins.
   virtual void AcceleratedSurfaceBuffersSwapped(
       const GpuHostMsg_AcceleratedSurfaceBuffersSwapped_Params& params,
       int gpu_host_id) = 0;
+  // Similar to above, except |params.(x|y|width|height)| define the region
+  // of the surface that changed.
+  virtual void AcceleratedSurfacePostSubBuffer(
+      const GpuHostMsg_AcceleratedSurfacePostSubBuffer_Params& params,
+      int gpu_host_id) = 0;
 
 #if defined(OS_MACOSX)
   // Tells the view whether or not to accept first responder status.  If |flag|
   // is true, the view does not accept first responder status and instead
   // manually becomes first responder when it receives a mouse down event.  If
   // |flag| is false, the view participates in the key-view chain as normal.
   virtual void SetTakesFocusOnlyOnMouseDown(bool flag) = 0;
 
   // Retrieve the bounds of the view, in cocoa view coordinates.
   // If the UI scale factor is 2, |GetViewBounds()| will return a size of e.g.
@@ skipping 144 matching lines @@
   size_t selection_text_offset_;
 
   // The current selection range relative to the start of the web page.
   ui::Range selection_range_;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(RenderWidgetHostView);
 };
 
 #endif  // CONTENT_BROWSER_RENDERER_HOST_RENDER_WIDGET_HOST_VIEW_H_