Move Field Trial Utils from chrome/common/variations to components/variations/field_trial_util

components/variations/fieldtrial_testing_config_schema.json

 // Copyright 2015 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.
 
 {
   "type_name": "FieldTrialTestingConfig",
   "schema": [{
     "field": "studies",
     "type": "array",
     "contents": {
@@ skipping 35 matching lines @@
                 "field": "forcing_flag",
                 "type": "string"
               }
             ]
           }
         }
       ]
     }
   }]
 }