[Sync] Add support for identifying tabbed activites

chrome/browser/ui/android/tab_model/tab_model.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_ANDROID_TAB_MODEL_TAB_MODEL_H_
 #define CHROME_BROWSER_UI_ANDROID_TAB_MODEL_TAB_MODEL_H_
 
 #include <memory>
 
 #include "base/macros.h"
@@ skipping 31 matching lines @@
   virtual SessionID::id_type GetSessionId() const;
   virtual const SessionID& SessionId() const;
   virtual sessions::LiveTabContext* GetLiveTabContext() const;
 
   virtual int GetTabCount() const = 0;
   virtual int GetActiveIndex() const = 0;
   virtual content::WebContents* GetActiveWebContents() const;
   virtual content::WebContents* GetWebContentsAt(int index) const = 0;
   // This will return NULL if the tab has not yet been initialized.
   virtual TabAndroid* GetTabAt(int index) const = 0;
+  virtual bool IsTabbedActivity() const = 0;
 
   virtual void SetActiveIndex(int index) = 0;
   virtual void CloseTabAt(int index) = 0;
 
   // Used for restoring tabs from synced foreign sessions.
   virtual void CreateTab(TabAndroid* parent,
                          content::WebContents* web_contents,
                          int parent_tab_id) = 0;
 
   // Used by Developer Tools to create a new tab with a given URL.
@@ skipping 38 matching lines @@
   // across sessions.
   SessionID session_id_;
 
   // The Registrar used to register TabModel for notifications.
   content::NotificationRegistrar registrar_;
 
   DISALLOW_COPY_AND_ASSIGN(TabModel);
 };
 
 #endif  // CHROME_BROWSER_UI_ANDROID_TAB_MODEL_TAB_MODEL_H_