[MD] Share button code between find bar and download shelf

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 2089 matching lines @@
       'browser/ui/views/autofill/info_bubble.cc',
       'browser/ui/views/autofill/info_bubble.h',
       'browser/ui/views/autofill/new_credit_card_bubble_views.cc',
       'browser/ui/views/autofill/new_credit_card_bubble_views.h',
       'browser/ui/views/autofill/password_generation_popup_view_views.cc',
       'browser/ui/views/autofill/password_generation_popup_view_views.h',
       'browser/ui/views/autofill/save_card_bubble_views.cc',
       'browser/ui/views/autofill/save_card_bubble_views.h',
       'browser/ui/views/autofill/tooltip_icon.cc',
       'browser/ui/views/autofill/tooltip_icon.h',
+      'browser/ui/views/bar_control_button.cc',
+      'browser/ui/views/bar_control_button.h',
       'browser/ui/views/bookmarks/bookmark_bar_instructions_view.cc',
       'browser/ui/views/bookmarks/bookmark_bar_instructions_view.h',
       'browser/ui/views/bookmarks/bookmark_bar_view.cc',
       'browser/ui/views/bookmarks/bookmark_bar_view.h',
       'browser/ui/views/bookmarks/bookmark_bar_view_observer.h',
       'browser/ui/views/bookmarks/bookmark_context_menu.cc',
       'browser/ui/views/bookmarks/bookmark_context_menu.h',
       'browser/ui/views/bookmarks/bookmark_drag_drop_views.cc',
       'browser/ui/views/bookmarks/bookmark_menu_controller_observer.h',
       'browser/ui/views/bookmarks/bookmark_menu_controller_views.cc',
@@ skipping 1128 matching lines @@
           ],
           'sources': [
             '<@(chrome_browser_ui_non_mobile_sources)',
             '<@(chrome_browser_ui_omnibox_non_mobile_sources)',
           ],
         }],
       ],
     },
   ],
 }