Allow dynamic switching in and out of sidetabs mode.

chrome/browser/tabs/tab_strip_model.h

 // Copyright (c) 2006-2008 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_TABS_TAB_STRIP_MODEL_H_
 #define CHROME_BROWSER_TABS_TAB_STRIP_MODEL_H_
 
 #include <vector>
 
 #include "base/observer_list.h"
@@ skipping 205 matching lines @@
 
   // Returns whether some contents can be closed.
   virtual bool CanCloseContentsAt(int index) = 0;
 
   // Returns true if we should allow "bookmark all tabs" in this window; this is
   // true when there is more than one bookmarkable tab open.
   virtual bool CanBookmarkAllTabs() const = 0;
 
   // Creates a bookmark folder containing a bookmark for all open tabs.
   virtual void BookmarkAllTabs() = 0;
+
+  // Returns true if the vertical tabstrip presentation should be used.
+  virtual bool UseVerticalTabs() const = 0;
+
+  // Toggles the use of the vertical tabstrip.
+  virtual void ToggleUseVerticalTabs() = 0;
 };
 
 ////////////////////////////////////////////////////////////////////////////////
 //
 // TabStripModel
 //
 //  A model & low level controller of a Browser Window tabstrip. Holds a vector
 //  of TabContents, and provides an API for adding, removing and shuffling
 //  them, as well as a higher level API for doing specific Browser-related
 //  tasks like adding new Tabs from just a URL, etc.
@@ skipping 304 matching lines @@
     CommandNewTab,
     CommandReload,
     CommandDuplicate,
     CommandCloseTab,
     CommandCloseOtherTabs,
     CommandCloseTabsToRight,
     CommandCloseTabsOpenedBy,
     CommandRestoreTab,
     CommandTogglePinned,
     CommandBookmarkAllTabs,
+    CommandUseVerticalTabs,
     CommandLast
   };
 
   // Returns true if the specified command is enabled.
   bool IsContextMenuCommandEnabled(int context_index,
                                    ContextMenuCommand command_id) const;
 
+  // Returns true if the specified command is checked.
+  bool IsContextMenuCommandChecked(int context_index,
+                                   ContextMenuCommand command_id) const;
+
   // Performs the action associated with the specified command for the given
   // TabStripModel index |context_index|.
   void ExecuteContextMenuCommand(int context_index,
                                  ContextMenuCommand command_id);
 
   // Returns a vector of indices of TabContentses opened from the TabContents
   // at the specified |index|.
   std::vector<int> GetIndexesOpenedBy(int index) const;
 
   // Overridden from notificationObserver:
@@ skipping 162 matching lines @@
   typedef ObserverList<TabStripModelObserver> TabStripModelObservers;
   TabStripModelObservers observers_;
 
   // A scoped container for notification registries.
   NotificationRegistrar registrar_;
 
   DISALLOW_COPY_AND_ASSIGN(TabStripModel);
 };
 
 #endif  // CHROME_BROWSER_TABS_TAB_STRIP_MODEL_H_