Remove RenderWidget::SetBackground, change IPC to pass a bool.

chrome/browser/chromeos/login/webui_login_view.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 "chrome/browser/chromeos/login/webui_login_view.h"
 
 #include "ash/shell.h"
 #include "ash/system/tray/system_tray.h"
 #include "base/bind.h"
 #include "base/callback.h"
@@ skipping 242 matching lines @@
 gfx::NativeWindow WebUILoginView::GetNativeWindow() const {
   return GetWidget()->GetNativeWindow();
 }
 
 void WebUILoginView::LoadURL(const GURL & url) {
   webui_login_->LoadInitialURL(url);
   webui_login_->RequestFocus();
 
   // TODO(nkostylev): Use WebContentsObserver::RenderViewCreated to track
   // when RenderView is created.
-  // Use a background with transparency to trigger transparency in Webkit.
-  SkBitmap background;
-  background.setConfig(SkBitmap::kARGB_8888_Config, 1, 1);
-  background.allocPixels();
-  background.eraseARGB(0x00, 0x00, 0x00, 0x00);
-  content::RenderViewHost* host = GetWebContents()->GetRenderViewHost();
-  host->GetView()->SetBackground(background);
+  GetWebContents()->GetRenderViewHost()->GetView()->SetBackgroundOpaque(false);
 }
 
 content::WebUI* WebUILoginView::GetWebUI() {
   return webui_login_->web_contents()->GetWebUI();
 }
 
 content::WebContents* WebUILoginView::GetWebContents() {
   return webui_login_->web_contents();
 }
 
@@ skipping 177 matching lines @@
   webui_visible_ = true;
 }
 
 void WebUILoginView::ReturnFocus(bool reverse) {
   // Return the focus to the web contents.
   webui_login_->web_contents()->FocusThroughTabTraversal(reverse);
   GetWidget()->Activate();
 }
 
 }  // namespace chromeos