Smooth Tab Switching on aura.

content/browser/renderer_host/render_widget_host_view_aura.cc

 // 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.
 
 #include "content/browser/renderer_host/render_widget_host_view_aura.h"
 
 #include "base/bind.h"
 #include "base/bind_helpers.h"
 #include "base/command_line.h"
 #include "base/logging.h"
@@ skipping 265 matching lines @@
   Show();
   Focus();
 }
 
 RenderWidgetHost* RenderWidgetHostViewAura::GetRenderWidgetHost() const {
   return host_;
 }
 
 void RenderWidgetHostViewAura::DidBecomeSelected() {
   host_->WasRestored();
+  if (!current_surface_ && host_->is_accelerated_compositing_active() &&
+      !released_front_lock_.get())
+    released_front_lock_ = window_->GetRootWindow()->GetCompositorLock();
 }
 
 void RenderWidgetHostViewAura::WasHidden() {
   host_->WasHidden();
+  released_front_lock_ = NULL;
 }
 
 void RenderWidgetHostViewAura::SetSize(const gfx::Size& size) {
   SetBounds(gfx::Rect(window_->bounds().origin(), size));
 }
 
 void RenderWidgetHostViewAura::SetBounds(const gfx::Rect& rect) {
   if (window_->bounds().size() != rect.size() &&
       host_->is_accelerated_compositing_active()) {
     resize_locks_.push_back(make_linked_ptr(
@@ skipping 202 matching lines @@
   needs_update_texture_ = false;
   if (current_surface_ != 0 &&
       host_->is_accelerated_compositing_active()) {
 
     ImageTransportClient* container =
         image_transport_clients_[current_surface_];
     if (container)
       container->Update();
     window_->SetExternalTexture(container);
 
+    released_front_lock_ = NULL;
+
     if (!container) {
       resize_locks_.clear();
     } else {
       typedef std::vector<linked_ptr<ResizeLock> > ResizeLockList;
       ResizeLockList::iterator it = resize_locks_.begin();
       while (it != resize_locks_.end()) {
         gfx::Size container_size = content::ConvertSizeToDIP(this,
             container->size());
         if ((*it)->expected_size() == container_size)
           break;
@@ skipping 822 matching lines @@
 RenderWidgetHostView* RenderWidgetHostView::CreateViewForWidget(
     RenderWidgetHost* widget) {
   return new RenderWidgetHostViewAura(widget);
 }
 
 // static
 void content::RenderWidgetHostViewPort::GetDefaultScreenInfo(
     WebKit::WebScreenInfo* results) {
   GetScreenInfoForWindow(results, NULL);
 }