Move gtk-specific browser main parts stuff to its own file.

chrome/browser/ui/libgtk2ui/libgtk2ui.gyp

 # 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.
 
 {
   'variables': {
     'chromium_code': 1,
   },
   'targets': [
     {
@@ skipping 34 matching lines @@
       # differentiate them from their source files (ninja and make are sane
       # build systems, unlike MSVS). It is instead to get around the rest of
       # the normal, global gtk exclusion rules, as we are otherwise using gtk
       # in a non-gtk build.
       'sources': [
         # Note: sources list duplicated in GN build.
         'app_indicator_icon.cc',
         'app_indicator_icon.h',
         'app_indicator_icon_menu.cc',
         'app_indicator_icon_menu.h',
+        'chrome_browser_main_extra_parts_views_gtk.cc',
+        'chrome_browser_main_extra_parts_views_gtk.h',
         'chrome_gtk_frame.cc',
         'chrome_gtk_frame.h',
         'chrome_gtk_menu_subclasses.cc',
         'chrome_gtk_menu_subclasses.h',
         'gconf_listener.cc',
         'gconf_listener.h',
         'gtk2_event_loop.cc',
         'gtk2_event_loop.h',
         'gtk2_key_bindings_handler.cc',
         'gtk2_key_bindings_handler.h',
@@ skipping 59 matching lines @@
         }],
         ['use_cups==1', {
           'dependencies': [
             '../../../../printing/printing.gyp:cups',
           ],
         }],
       ],
     },
   ],
 }