Creates BrowserTabStripTracker to consolidate common code

chrome/chrome_browser_ui.gypi

 # Copyright 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.
 
 {
   'variables': {
     # There are two sections of sources:
     # * "Platform"-based sources (OS, toolkit, etc.)
     # * Feature/directory-based sources (e.g., history, printing)
 
@@ skipping 1499 matching lines @@
       'browser/ui/browser_list.h',
       'browser/ui/browser_navigator.cc',
       'browser/ui/browser_navigator.h',
       'browser/ui/browser_live_tab_context.cc',
       'browser/ui/browser_live_tab_context.h',
       'browser/ui/browser_otr_state.cc',
       'browser/ui/browser_otr_state.h',
       'browser/ui/browser_tab_restorer.cc',
       'browser/ui/browser_tab_strip_model_delegate.cc',
       'browser/ui/browser_tab_strip_model_delegate.h',
+      'browser/ui/browser_tab_strip_tracker.cc',
+      'browser/ui/browser_tab_strip_tracker.h',
+      'browser/ui/browser_tab_strip_tracker_delegate.h',
       'browser/ui/browser_tabrestore.cc',
       'browser/ui/browser_tabrestore.h',
       'browser/ui/browser_tabstrip.cc',
       'browser/ui/browser_tabstrip.h',
       'browser/ui/browser_toolbar_model_delegate.cc',
       'browser/ui/browser_toolbar_model_delegate.h',
       'browser/ui/browser_view_prefs.cc',
       'browser/ui/browser_view_prefs.h',
       'browser/ui/browser_window_state.cc',
       'browser/ui/browser_window_state.h',
@@ skipping 1696 matching lines @@
           ],
           'sources': [
             '<@(chrome_browser_ui_non_mobile_sources)',
             '<@(chrome_browser_ui_omnibox_non_mobile_sources)',
           ],
         }],
       ],
     },
   ],
 }