Switch ExternalProtocolObserver to use WebContentsUserData.

chrome/browser/ui/tab_contents/tab_contents.h

 // 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.
 
 #ifndef CHROME_BROWSER_UI_TAB_CONTENTS_TAB_CONTENTS_H_
 #define CHROME_BROWSER_UI_TAB_CONTENTS_TAB_CONTENTS_H_
 
 #include "base/basictypes.h"
 #include "base/compiler_specific.h"
 #include "base/gtest_prod_util.h"
 #include "base/memory/ref_counted.h"
 #include "base/memory/scoped_ptr.h"
 #include "content/public/browser/web_contents_observer.h"
 
 class AutocompleteHistoryManager;
 class AutofillExternalDelegate;
 class AutofillManager;
 class AutomationTabHelper;
 class BasePanelBrowserTest;
 class Browser;
 class BrowserCommandsTabContentsCreator;
 class BrowserLauncherItemControllerContentsCreator;
 class BrowserTabstripTabContentsCreator;
 class ChromeWebContentsHandler;
 class ConstrainedWebDialogDelegateBase;
 class ConstrainedWindowTabHelper;
 class ExtensionTabUtil;
-class ExternalProtocolObserver;
 class ExternalTabContainerWin;
 class FaviconTabHelper;
 class FindBackendTestContentsCreator;
 class FindTabHelper;
 class GeolocationPermissionContextTests;
 class HistoryTabHelper;
 class InfoBarControllerContentsCreator;
 class InfoBarTabHelper;
 class InstantLoader;
 class NavigationMetricsRecorder;
@@ skipping 213 matching lines @@
   // state by various UI elements.
   scoped_ptr<TabSpecificContentSettings> content_settings_;
 
   scoped_ptr<ThumbnailGenerator> thumbnail_generator_;
   scoped_ptr<TranslateTabHelper> translate_tab_helper_;
 
   // Per-tab observers ---------------------------------------------------------
   // (These provide no API for callers; objects that need to exist 1:1 with tabs
   // and silently do their thing live here.)
 
-  scoped_ptr<ExternalProtocolObserver> external_protocol_observer_;
   scoped_ptr<NavigationMetricsRecorder> navigation_metrics_recorder_;
   scoped_ptr<PepperBrokerObserver> pepper_broker_observer_;
   scoped_ptr<safe_browsing::SafeBrowsingTabObserver>
       safe_browsing_tab_observer_;
 
   // WebContents (MUST BE LAST) ------------------------------------------------
 
   // If true, we're running the destructor.
   bool in_destructor_;
 
   // The supporting objects need to outlive the WebContents dtor (as they may
   // be called upon during its execution). As a result, this must come last
   // in the list.
   scoped_ptr<content::WebContents> web_contents_;
 
   DISALLOW_COPY_AND_ASSIGN(TabContents);
 };
 
 #endif  // CHROME_BROWSER_UI_TAB_CONTENTS_TAB_CONTENTS_H_