Update GN build files for new prefs location.

components/browser_sync/browser/BUILD.gn

 # 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.
 
 import("//build/config/features.gni")
 
 source_set("browser") {
   sources = [
     "profile_sync_components_factory_impl.cc",
     "profile_sync_components_factory_impl.h",
     "profile_sync_service.cc",
     "profile_sync_service.h",
     "signin_confirmation_helper.cc",
     "signin_confirmation_helper.h",
   ]
 
   deps = [
     "//base",
-    "//base:prefs",
     "//components/autofill/core/browser",
     "//components/autofill/core/common",
     "//components/browser_sync/common",
     "//components/dom_distiller/core",
     "//components/history/core/browser",
     "//components/invalidation/impl",
     "//components/invalidation/public",
     "//components/keyed_service/core",
     "//components/password_manager/core/browser",
     "//components/password_manager/sync/browser",
     "//components/pref_registry",
+    "//components/prefs",
     "//components/signin/core/browser",
     "//components/strings",
     "//components/sync_bookmarks",
     "//components/sync_driver",
     "//components/sync_sessions",
     "//components/syncable_prefs",
     "//components/variations",
     "//components/version_info",
     "//components/version_info:generate_version_info",
     "//google_apis",
@@ skipping 56 matching lines @@
     "//components/signin/core/browser:test_support",
     "//components/sync_driver",
     "//components/sync_driver:test_support",
     "//components/sync_sessions:test_support",
     "//components/syncable_prefs:test_support",
     "//google_apis",
     "//net:test_support",
     "//testing/gmock",
   ]
 }