Plumb the partial swap though image transport.

ui/gfx/gl/gl_surface.cc

 // 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.
 
 #include "ui/gfx/gl/gl_surface.h"
 
 #include <algorithm>
 #include <vector>
 
 #include "base/command_line.h"
@@ skipping 73 matching lines @@
 {
   return true;
 }
 
 bool GLSurface::Resize(const gfx::Size& size) {
   NOTIMPLEMENTED();
   return false;
 }
 
 std::string GLSurface::GetExtensions() {
-  DCHECK_EQ(GetCurrent(), this);
+  // Use of GLSurfaceAdapter class means that we can't compare
+  // GetCurrent() and this directly.
+  DCHECK_EQ(GetCurrent()->GetHandle(), GetHandle());
   return std::string("");
 }
 
 unsigned int GLSurface::GetBackingFrameBufferObject() {
   return 0;
 }
 
 bool GLSurface::PostSubBuffer(int x, int y, int width, int height) {
   return false;
 }
@@ skipping 52 matching lines @@
 }
 
 bool GLSurfaceAdapter::IsOffscreen() {
   return surface_->IsOffscreen();
 }
 
 bool GLSurfaceAdapter::SwapBuffers() {
   return surface_->SwapBuffers();
 }
 
+bool GLSurfaceAdapter::PostSubBuffer(int x, int y, int width, int height) {
+  return surface_->PostSubBuffer(x, y, width, height);
+}
+
+std::string GLSurfaceAdapter::GetExtensions() {
+  return surface_->GetExtensions();
+}
+
 gfx::Size GLSurfaceAdapter::GetSize() {
   return surface_->GetSize();
 }
 
 void* GLSurfaceAdapter::GetHandle() {
   return surface_->GetHandle();
 }
 
 unsigned int GLSurfaceAdapter::GetBackingFrameBufferObject() {
   return surface_->GetBackingFrameBufferObject();
@@ skipping 13 matching lines @@
 
 void* GLSurfaceAdapter::GetConfig() {
   return surface_->GetConfig();
 }
 
 unsigned GLSurfaceAdapter::GetFormat() {
   return surface_->GetFormat();
 }
 
 }  // namespace gfx