Add chrome://proximity-auth UI implemented with Polymer.

components/proximity_auth.gypi

 # 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.
 
 {
   'targets': [
     {
       'target_name': 'proximity_auth',
       'type': 'static_library',
       'include_dirs': [
@@ skipping 108 matching lines @@
         'cryptauth_proto',
       ],
     },
     {
       # GN version: //components/proximity_auth/webui
       'target_name': 'proximity_auth_webui',
       'type': 'static_library',
       'dependencies': [
         '../base/base.gyp:base',
         '../content/content.gyp:content_browser',
+        '../ui/resources/ui_resources.gyp:ui_resources',
         'components_resources.gyp:components_resources',
         'proximity_auth',
-        'cryptauth',
       ],
       'include_dirs': [
         '..',
       ],
       'sources': [
         'proximity_auth/webui/proximity_auth_ui.cc',
         'proximity_auth/webui/proximity_auth_ui.h',
         'proximity_auth/webui/proximity_auth_webui_handler.cc',
         'proximity_auth/webui/proximity_auth_webui_handler.h',
         'proximity_auth/webui/url_constants.cc',
         'proximity_auth/webui/url_constants.h',
       ],
     },
   ],
 }