Make using WebContentsUserData simpler.

chrome/browser/ui/search/search_tab_helper.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/ui/search/search_tab_helper.h"
 
 #include "chrome/browser/google/google_util.h"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/ui/search/search.h"
 #include "chrome/common/url_constants.h"
 #include "content/public/browser/navigation_controller.h"
 #include "content/public/browser/navigation_details.h"
 #include "content/public/browser/navigation_entry.h"
 #include "content/public/browser/notification_service.h"
 #include "content/public/browser/notification_types.h"
 #include "content/public/browser/render_widget_host_view.h"
 #include "content/public/browser/web_contents.h"
 
-int chrome::search::SearchTabHelper::kUserDataKey;
+DEFINE_WEB_CONTENTS_USER_DATA_KEY(chrome::search::SearchTabHelper)
 
 namespace {
 
 bool IsNTP(const GURL& url) {
   return url.SchemeIs(chrome::kChromeUIScheme) &&
          url.host() == chrome::kChromeUINewTabHost;
 }
 
 bool IsSearchEnabled(content::WebContents* web_contents) {
   Profile* profile =
@@ skipping 143 matching lines @@
 }
 
 content::RenderWidgetHost* SearchTabHelper::GetRenderWidgetHost() {
   content::RenderWidgetHostView* rwhv =
       web_contents()->GetRenderWidgetHostView();
   return rwhv ? rwhv->GetRenderWidgetHost() : NULL;
 }
 
 }  // namespace search
 }  // namespace chrome