clean up field_trial_default target

webrtc/system_wrappers/system_wrappers.gyp

 # Copyright (c) 2012 The WebRTC project authors. All Rights Reserved.
 #
 # Use of this source code is governed by a BSD-style license
 # that can be found in the LICENSE file in the root of the source
 # tree. An additional intellectual property rights grant can be found
 # in the file PATENTS.  All contributing project authors may
 # be found in the AUTHORS file in the root of the source tree.
 
 {
   'includes': [ '../build/common.gypi', ],
@@ skipping 181 matching lines @@
       'msvs_disabled_warnings': [
         4267,  # size_t to int truncation.
         4334,  # Ignore warning on shift operator promotion.
       ],
     }, {
       'target_name': 'field_trial_default',
       'type': 'static_library',
       'sources': [
         'interface/field_trial_default.h',
         'source/field_trial_default.cc',
-      ],
-      'dependencies': [
-        'system_wrappers',
       ]
     }, {
       'target_name': 'metrics_default',
       'type': 'static_library',
       'sources': [
         'source/metrics_default.cc',
       ],
       'dependencies': [
         'system_wrappers',
       ]
     }, {
       'target_name': 'system_wrappers_default',
       'type': 'static_library',
       'dependencies': [
         'field_trial_default',
         'metrics_default',
       ]
     },
   ], # targets
 }