Create GoogleURLTrackerClient interface and //chrome implementation

components/google.gypi

 # 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.
 
 {
   'targets': [
     {
       'target_name': 'google_core_browser',
       'type': 'static_library',
       'dependencies': [
         '../base/base.gyp:base',
       ],
       'include_dirs': [
         '..',
       ],
       'sources': [
         'google/core/browser/google_search_metrics.cc',
         'google/core/browser/google_search_metrics.h',
+        'google/core/browser/google_url_tracker_client.cc',
+        'google/core/browser/google_url_tracker_client.h',
       ],
     },
   ],
 }