Revert of Move base/prefs to components/prefs

ios/chrome/ios_chrome_tests.gyp

 # 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.
 {
   'variables': {
     'chromium_code': 1,
   },
   'targets': [
     {
       # GN version: //ios/chrome:ios_chrome_unittests
       'target_name': 'ios_chrome_unittests',
       'type': '<(gtest_target_type)',
       'dependencies': [
         '../../base/base.gyp:base',
+        '../../base/base.gyp:base_prefs_test_support',
         '../../base/base.gyp:test_support_base',
         '../../components/components.gyp:bookmarks_test_support',
         '../../components/components.gyp:favicon_base',
         '../../components/components.gyp:metrics',
         '../../components/components.gyp:metrics_test_support',
         '../../components/components.gyp:update_client',
         '../../components/components.gyp:version_info',
-        '../../components/prefs/prefs.gyp:prefs_test_support',
         '../../net/net.gyp:net_test_support',
         '../../skia/skia.gyp:skia',
         '../../testing/gmock.gyp:gmock',
         '../../testing/gtest.gyp:gtest',
         '../../third_party/ocmock/ocmock.gyp:ocmock',
         '../../ui/gfx/gfx.gyp:gfx',
         '../../ui/gfx/gfx.gyp:gfx_test_support',
         '../ios_tests.gyp:test_support_ios',
         '../web/ios_web.gyp:ios_web',
         '../web/ios_web.gyp:ios_web_test_support',
@@ skipping 97 matching lines @@
         'test/ios_chrome_scoped_testing_local_state.h',
         'test/ios_chrome_unit_test_suite.cc',
         'test/ios_chrome_unit_test_suite.h',
         'test/run_all_unittests.cc',
         'test/testing_application_context.cc',
         'test/testing_application_context.h',
       ],
     },
   ],
 }