Update GN build files for new prefs location.

extensions/BUILD.gn

 # 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.
 
 # TODO(rockot) bug 505926: Don't include chrome files from here.
 # See chrome_browser_tests_extensions_sources below
 import("//chrome/chrome_tests.gni")
 import("//extensions/extensions.gni")
 import("//testing/test.gni")
 import("//tools/grit/grit_rule.gni")
@@ skipping 63 matching lines @@
   sources = rebase_path(extensions_gypi_values.extensions_test_support_sources,
                         ".",
                         "//extensions")
 
   # TODO(jschuh): crbug.com/167187 fix size_t to int truncations.
   configs += [ "//build/config/compiler:no_size_t_to_int_warning" ]
 
   deps = [
     ":extensions_resources",
     "//base",
-    "//base:prefs_test_support",
     "//components/guest_view/browser:test_support",
     "//components/pref_registry:test_support",
+    "//components/prefs:test_support",
     "//content/public/common",
     "//content/test:test_support",
     "//extensions/browser",
     "//extensions/common",
     "//extensions/common/api",
     "//extensions/common/api:api_registration",
     "//net:test_support",
     "//testing/gmock",
     "//testing/gtest",
   ]
@@ skipping 71 matching lines @@
     "test/data/",
     "//chrome/test/data/extensions/",
     "$root_out_dir/extensions_shell_and_test.pak",
   ]
 
   deps = [
     ":extensions_resources",
     ":shell_and_test_pak",
     ":test_support",
     "//base",
-    "//base:prefs_test_support",
     "//base/test:test_support",
     "//components/keyed_service/content",
     "//components/pref_registry:test_support",
+    "//components/prefs:test_support",
     "//components/user_prefs",
     "//content/test:test_support",
     "//device/bluetooth:mocks",
     "//device/core",
     "//device/hid",
     "//device/serial",
     "//device/serial:test_support",
     "//extensions/common",
     "//extensions/common/api/cast_channel:cast_channel_proto",
     "//extensions/renderer",
@@ skipping 52 matching lines @@
   ]
 
   defines = [ "HAS_OUT_OF_PROC_TEST_RUNNER" ]
 
   deps = [
     ":test_support",
     "shell:app_shell_lib",
 
     # TODO(yoz): find the right deps
     "//base",
-    "//base:prefs_test_support",
     "//base/test:test_support",
+    "//components/prefs:test_support",
     "//components/storage_monitor:test_support",
     "//content/test:test_support",
     "//device/bluetooth:mocks",
     "//device/core:mocks",
     "//device/hid:mocks",
     "//device/usb:mocks",
     "//mojo/environment:chromium",
     "//mojo/public/cpp/bindings",
     "//testing/gmock",
     "//testing/gtest",
@@ skipping 120 matching lines @@
     "//testing/gtest",
     "//third_party/hunspell",
     "//third_party/icu",
     "//third_party/libpng",
     "//third_party/zlib",
     "//ui/base:test_support",
     "//ui/resources:ui_test_pak",
     "//ui/web_dialogs:test_support",
   ]
 }