Add a flag that lets the webstore show a different UI on app install.

chrome/browser/ui/views/tabs/tab_strip.h

 // Copyright (c) 2011 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_VIEWS_TABS_TAB_STRIP_H_
 #define CHROME_BROWSER_UI_VIEWS_TABS_TAB_STRIP_H_
 #pragma once
 
 #include "base/memory/ref_counted.h"
 #include "base/timer.h"
@@ skipping 36 matching lines @@
 
   // Does he new tab button need to be sized to the top of the tab strip?
   bool SizeTabButtonToTopOfTabStrip();
 
   // MouseWatcherListener overrides:
   virtual void MouseMovedOutOfView() OVERRIDE;
 
   // AbstractTabStripView implementation:
   virtual bool IsPositionInWindowCaption(const gfx::Point& point) OVERRIDE;
   virtual void SetBackgroundOffset(const gfx::Point& offset) OVERRIDE;
+  virtual views::View* GetNewTabButton() OVERRIDE;
 
   // BaseTabStrip implementation:
   virtual void PrepareForCloseAt(int model_index) OVERRIDE;
   virtual void RemoveTabAt(int model_index) OVERRIDE;
   virtual void SetSelection(
       const TabStripSelectionModel& old_selection,
       const TabStripSelectionModel& new_selection) OVERRIDE;
   virtual void TabTitleChangedNotLoading(int model_index) OVERRIDE;
   virtual void StartHighlight(int model_index) OVERRIDE;
   virtual void StopAllHighlighting() OVERRIDE;
@@ skipping 201 matching lines @@
 
   // Used for stage 1 of new tab animation.
   base::OneShotTimer<TabStrip> new_tab_timer_;
 
   scoped_ptr<views::MouseWatcher> mouse_watcher_;
 
   DISALLOW_COPY_AND_ASSIGN(TabStrip);
 };
 
 #endif  // CHROME_BROWSER_UI_VIEWS_TABS_TAB_STRIP_H_