gpu: Fix dependency cycle between service_sources and config_sources.

gpu/gpu.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': {
     'nacl_win64_target': 0,
   },
   'includes': [
     'gpu_common.gypi',
@@ skipping 484 matching lines @@
           'includes': [
             'command_buffer_service.gypi',
             '../build/android/increase_size_for_speed.gypi',
             # Disable LTO due to ELF section name out of range
             # crbug.com/422251
             '../build/android/disable_lto.gypi',
           ],
           'dependencies': [
             'command_buffer_common',
             'disk_cache_proto',
+            'gpu_config',
           ],
           # TODO(jschuh): crbug.com/167187 fix size_t to int truncations.
           'msvs_disabled_warnings': [4267, ],
         },
         {
           # GN version: //gpu/ipc
           'target_name': 'gpu_ipc',
           'type': 'static_library',
           'includes': [
             'gpu_ipc.gypi',
@@ skipping 242 matching lines @@
                   '../tools/xdisplaycheck/xdisplaycheck.gyp:xdisplaycheck',
                 ],
               }
             ],
           ],
         },
       ],
     }],
   ],
 }