ScreenContext is moved to components/login.

components/components.gyp

 # Copyright (c) 2013 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': {
     # This turns on e.g. the filename-based detection of which
     # platforms to include source files on (e.g. files ending in
     # _mac.h or _mac.cc are only compiled on MacOSX).
     'chromium_code': 1,
@@ skipping 16 matching lines @@
     'error_page.gypi',
     'favicon.gypi',
     'favicon_base.gypi',
     'google.gypi',
     'history.gypi',
     'infobars.gypi',
     'json_schema.gypi',
     'keyed_service.gypi',
     'language_usage_metrics.gypi',
     'leveldb_proto.gypi',
+    'login.gypi',
     'metrics.gypi',
     'navigation_metrics.gypi',
     'network_time.gypi',
     'omaha_query_params.gypi',
     'onc.gypi',
     'os_crypt.gypi',
     'ownership.gypi',
     'password_manager.gypi',
     'policy.gypi',
     'precache.gypi',
@@ skipping 68 matching lines @@
         'invalidation.gypi',
       ],
     }],
     ['enable_plugins==1', {
       'includes': [
         'pdf.gypi',
       ],
     }],
   ],
 }