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

chrome/browser/ui/views/tabs/side_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_SIDE_TAB_STRIP_H_
 #define CHROME_BROWSER_UI_VIEWS_TABS_SIDE_TAB_STRIP_H_
 #pragma once
 
 #include "chrome/browser/ui/views/tabs/base_tab_strip.h"
 #include "views/controls/button/button.h"
 
 struct TabRendererData;
 class TabStripSelectionModel;
 
 class SideTabStrip : public BaseTabStrip, public views::ButtonListener {
  public:
   // The tabs are inset by this much along all axis.
   static const int kTabStripInset;
 
   explicit SideTabStrip(TabStripController* controller);
   virtual ~SideTabStrip();
 
   // 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 StartHighlight(int model_index) OVERRIDE;
   virtual void StopAllHighlighting() OVERRIDE;
   virtual BaseTab* CreateTabForDragging() 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;
@@ skipping 62 matching lines @@
   int first_tab_y_offset_;
 
   // Height needed to display the tabs, separator and new tab button. Doesn't
   // include any padding.
   int ideal_height_;
 
   DISALLOW_COPY_AND_ASSIGN(SideTabStrip);
 };
 
 #endif  // CHROME_BROWSER_UI_VIEWS_TABS_SIDE_TAB_STRIP_H_