Update GN build files for new prefs location.

components/sync_bookmarks/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("sync_bookmarks") {
   sources = [
     "bookmark_change_processor.cc",
     "bookmark_change_processor.h",
@@ skipping 18 matching lines @@
 source_set("unit_tests") {
   testonly = true
 
   sources = [
     "bookmark_data_type_controller_unittest.cc",
   ]
 
   deps = [
     ":sync_bookmarks",
     "//base",
-    "//base:prefs_test_support",
     "//components/bookmarks/browser",
     "//components/bookmarks/test",
     "//components/history/core/browser",
+    "//components/prefs:test_support",
     "//components/sync_driver",
     "//components/sync_driver:test_support",
     "//sync",
     "//testing/gmock",
     "//testing/gtest",
   ]
 }