Separate athena's startup process from AppShell's

athena/main/athena_main.gyp

 # Copyright 2014 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 45 matching lines @@
       'dependencies': [
         '../../ui/accessibility/accessibility.gyp:ax_gen',
         '../resources/athena_resources.gyp:athena_pak',
         '../../extensions/shell/app_shell.gyp:app_shell_lib',
         'athena_main_lib',
       ],
       'include_dirs': [
         '../..',
       ],
       'sources': [
-        'athena_app_window_controller.cc',
-        'athena_app_window_controller.h',
         'athena_main.cc',
       ],
     }
   ],  # targets
 }