Move ProxyServiceFactory to components/proxy_service/ios.

ios/chrome/browser/browser_state/BUILD.gn

 # Copyright 2016 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.
 
 source_set("browser_state") {
   sources = [
     "browser_state_otr_helper.cc",
     "browser_state_otr_helper.h",
     "chrome_browser_state.h",
     "chrome_browser_state.mm",
@@ skipping 51 matching lines @@
     "//components/cookie_config",
     "//components/invalidation/impl",
     "//components/keyed_service/ios",
     "//components/metrics",
     "//components/net_log",
     "//components/password_manager/core/browser",
     "//components/password_manager/sync/browser",
     "//components/pref_registry",
     "//components/prefs",
     "//components/proxy_config",
+    "//components/proxy_config/ios",
     "//components/signin/core/browser",
     "//components/signin/core/common",
     "//components/sync",
     "//components/sync_preferences",
     "//components/user_prefs",
     "//google_apis",
     "//ios/chrome/browser",
     "//ios/chrome/browser/autocomplete",
     "//ios/chrome/browser/autofill",
     "//ios/chrome/browser/bookmarks",
@@ skipping 74 matching lines @@
     "//ios/chrome/browser/sync/glue",
     "//ios/chrome/test:test_support",
     "//ios/public/provider/chrome/browser",
     "//ios/public/provider/chrome/browser/ui",
     "//ios/web",
     "//net:test_support",
   ]
 
   configs += [ "//build/config/compiler:enable_arc" ]
 }