Adding mojo calls for easy unlock service

components/proximity_auth/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")
 
 static_library("proximity_auth") {
   sources = [
     "bluetooth_connection.cc",
     "bluetooth_connection.h",
@@ skipping 34 matching lines @@
     "switches.cc",
     "switches.h",
     "throttled_bluetooth_connection_finder.cc",
     "throttled_bluetooth_connection_finder.h",
     "unlock_manager.h",
     "unlock_manager_impl.cc",
     "unlock_manager_impl.h",
   ]
 
   deps = [
+    "//ash/public/cpp:ash_public_cpp",

[xiyuan, 2017/06/05 17:30:40]

Not sure whether proximity_auth owner would be happen about this. We can put
ToUserPodCustomIconOptionsPtr in UserSelectionScreenProxy where it is needed to
avoid this deps for now.

The build failures might be caused by this since proximity_auth is available on
win/mac etc platforms but ash is chromeos only. 

     "//base",
     "//components/cryptauth",
     "//components/cryptauth/ble",
     "//components/prefs",
     "//components/proximity_auth/logging",
     "//components/signin/core/account_id:account_id",
     "//device/bluetooth",
     "//net",
   ]
 
@@ skipping 72 matching lines @@
     sources = [
       "run_all_unittests.cc",
     ]
     deps = [
       ":unit_tests",
       "//base",
       "//base/test:test_support",
     ]
   }
 }