Update GN build files for new prefs location.

components/proximity_auth/ble/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.
 
 import("//testing/test.gni")
 
 source_set("ble") {
   sources = [
     "bluetooth_low_energy_characteristics_finder.cc",
     "bluetooth_low_energy_characteristics_finder.h",
     "bluetooth_low_energy_connection.cc",
     "bluetooth_low_energy_connection.h",
     "bluetooth_low_energy_connection_finder.cc",
     "bluetooth_low_energy_connection_finder.h",
     "bluetooth_low_energy_device_whitelist.cc",
     "bluetooth_low_energy_device_whitelist.h",
     "fake_wire_message.cc",
     "fake_wire_message.h",
     "pref_names.cc",
     "pref_names.h",
     "remote_attribute.h",
   ]
 
   deps = [
     "//base",
-    "//base:prefs",
+    "//components/prefs",
     "//components/proximity_auth/logging",
 
     # TODO(https://crbug.com/562683): This component has a circular dependency
     # with the root proximity auth target. It is whitelisted in that target for
     # includes.
     #"//components/proximity_auth",
     "//device/bluetooth",
     "//net",
   ]
 
   public_deps = [
     "//components/proximity_auth/cryptauth/proto",
   ]
 }
 
 source_set("unit_tests") {
   testonly = true
   sources = [
     "bluetooth_low_energy_characteristics_finder_unittest.cc",
     "bluetooth_low_energy_connection_finder_unittest.cc",
     "bluetooth_low_energy_connection_unittest.cc",
     "bluetooth_low_energy_device_whitelist_unittest.cc",
   ]
 
   configs += [ "//build/config/compiler:no_size_t_to_int_warning" ]
 
   deps = [
     ":ble",
-    "//base:prefs_test_support",
     "//base/test:test_support",
+    "//components/prefs:test_support",
     "//components/proximity_auth:test_support",
     "//device/bluetooth:mocks",
     "//testing/gmock",
     "//testing/gtest",
   ]
 
   public_deps = [
     "//components/proximity_auth/cryptauth/proto",
   ]
 }