Fix remaining shared_library link_settings propagation

sync/sync_core.gypi

 # Copyright 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.
 
 {
   'include_dirs': [
     '..',
   ],
   'defines': [
     'SYNC_IMPLEMENTATION',
   ],
   'dependencies': [
     '../base/base.gyp:base',
     '../base/base.gyp:base_i18n',
     '../crypto/crypto.gyp:crypto',
     '../google_apis/google_apis.gyp:google_apis',
     '../net/net.gyp:net',
     '../sql/sql.gyp:sql',
     '../url/url.gyp:url_lib',
   ],
   'conditions': [
     ['OS=="linux" and chromeos==1', {
       # Required by get_session_name.cc on Chrome OS.
       'dependencies': [
         '../chromeos/chromeos.gyp:chromeos',
       ],
     }],
+    ['OS=="mac"', {
+      'link_settings': {
+        'libraries': [
+          '$(SDKROOT)/System/Library/Frameworks/SystemConfiguration.framework',
+        ],
+      },
+    }],
   ],
   'sources': [
     'base/sync_export.h',
     'engine/all_status.cc',
     'engine/all_status.h',
     'engine/apply_control_data_updates.cc',
     'engine/apply_control_data_updates.h',
     'engine/apply_updates_and_resolve_conflicts_command.cc',
     'engine/apply_updates_and_resolve_conflicts_command.h',
     'engine/backoff_delay_provider.cc',
@@ skipping 150 matching lines @@
     'util/get_session_name_win.cc',
     'util/get_session_name_win.h',
     'util/logging.cc',
     'util/logging.h',
     'util/nigori.cc',
     'util/nigori.h',
     'util/time.cc',
     'util/time.h',
   ],
 }