Add gn implementation of //ios/public/provider/chrome/browser.

ios/provider/ios_provider_chrome.gyp

 # Copyright 2013 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.
 {
   'variables': {
     'chromium_code': 1,
    },
   'targets': [
     {
+      # GN version: //ios/public/provider/chrome/browser
       'target_name': 'ios_provider_chrome_browser',
       'type': 'static_library',
       'sources': [
         '../public/provider/chrome/browser/browser_state/chrome_browser_state.cc',
         '../public/provider/chrome/browser/browser_state/chrome_browser_state.h',
         '../public/provider/chrome/browser/browser_state/chrome_browser_state_manager.h',
         '../public/provider/chrome/browser/chrome_browser_provider.cc',
         '../public/provider/chrome/browser/chrome_browser_provider.h',
         '../public/provider/chrome/browser/geolocation_updater_provider.h',
         '../public/provider/chrome/browser/geolocation_updater_provider.mm',
@@ skipping 13 matching lines @@
       ],
       'dependencies': [
         '../../base/base.gyp:base',
         '../../components/components.gyp:autofill_core_browser',
         '../web/ios_web.gyp:ios_web',
         'ios_provider_web.gyp:ios_provider_web',
       ],
     },
   ],
 }