Pulling user experiment code from BrowserDistribution to a new class.

chrome/chrome_installer_util.gypi

 # 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.
 
 {
   'target_defaults': {
     'variables': {
       'installer_util_target': 0,
     },
     'target_conditions': [
@@ skipping 136 matching lines @@
             'installer/util/lzma_util.h',
             'installer/util/master_preferences.cc',
             'installer/util/master_preferences.h',
             'installer/util/product.h',
             'installer/util/product.cc',
             'installer/util/product_operations.h',
             'installer/util/self_cleaning_temp_dir.cc',
             'installer/util/self_cleaning_temp_dir.h',
             'installer/util/shell_util.cc',
             'installer/util/shell_util.h',
+            'installer/util/user_experiment.cc',
+            'installer/util/user_experiment.h',
           ],
           'conditions': [
             ['component=="shared_library"', {
               'sources': [ '../content/public/common/content_switches.cc' ],
               'defines': [ 'COMPILE_CONTENT_STATICALLY'],
             }, {
               'dependencies': ['<(DEPTH)/content/content.gyp:content_common'],
             }],
           ],
           # TODO(jschuh): crbug.com/167187 fix size_t to int truncations.
@@ skipping 52 matching lines @@
               'sources': [ '../content/public/common/content_switches.cc' ],
               'defines': [ 'COMPILE_CONTENT_STATICALLY'],
             }],
           ],
         }
       ],
     }],
 
   ],
 }