Allow secondary tiles to be unpinned.

chrome/chrome_browser.gypi

 # 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.
 
 {
   'targets': [
     {
       'target_name': 'browser',
       'type': 'static_library',
@@ skipping 3228 matching lines @@
         'browser/ui/intents/web_intent_picker_model.cc',
         'browser/ui/intents/web_intent_picker_model.h',
         'browser/ui/intents/web_intent_picker_model_observer.h',
         'browser/ui/intents/web_intents_model.cc',
         'browser/ui/intents/web_intents_model.h',
         'browser/ui/login/login_model.h',
         'browser/ui/login/login_prompt.cc',
         'browser/ui/login/login_prompt.h',
         'browser/ui/media_stream_infobar_delegate.h',
         'browser/ui/media_stream_infobar_delegate.cc',
+        'browser/ui/metro_pin_tab_helper.cc',
+        'browser/ui/metro_pin_tab_helper.h',
         'browser/ui/network_profile_bubble.cc',
         'browser/ui/network_profile_bubble.h',
         'browser/ui/omnibox/location_bar.h',
         'browser/ui/omnibox/location_bar_util.cc',
         'browser/ui/omnibox/location_bar_util.h',
         'browser/ui/omnibox/omnibox_edit_controller.h',
         'browser/ui/omnibox/omnibox_edit_model.cc',
         'browser/ui/omnibox/omnibox_edit_model.h',
         'browser/ui/omnibox/omnibox_popup_model.cc',
         'browser/ui/omnibox/omnibox_popup_model.h',
@@ skipping 2156 matching lines @@
         'browser/metrics/proto/study.proto',
       ],
       'variables': {
         'proto_in_dir': 'browser/metrics/proto',
         'proto_out_dir': 'chrome/browser/metrics/proto',
       },
       'includes': [ '../build/protoc.gypi' ]
     },
   ],
 }