Use mojo SystemTray interfaces for both mash and classic ash

ash/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("//build/config/features.gni")
 import("//build/config/ui.gni")
 import("//testing/test.gni")
 import("//ui/base/ui_features.gni")
 
 assert(use_aura)
@@ skipping 338 matching lines @@
     "common/system/tray/label_tray_view.cc",
     "common/system/tray/label_tray_view.h",
     "common/system/tray/special_popup_row.cc",
     "common/system/tray/special_popup_row.h",
     "common/system/tray/system_menu_button.cc",
     "common/system/tray/system_menu_button.h",
     "common/system/tray/system_tray.cc",
     "common/system/tray/system_tray.h",
     "common/system/tray/system_tray_bubble.cc",
     "common/system/tray/system_tray_bubble.h",
+    "common/system/tray/system_tray_controller.cc",
+    "common/system/tray/system_tray_controller.h",
     "common/system/tray/system_tray_delegate.cc",
     "common/system/tray/system_tray_delegate.h",
     "common/system/tray/system_tray_item.cc",
     "common/system/tray/system_tray_item.h",
     "common/system/tray/system_tray_notifier.cc",
     "common/system/tray/system_tray_notifier.h",
     "common/system/tray/throbber_view.cc",
     "common/system/tray/throbber_view.h",
     "common/system/tray/tray_background_view.cc",
     "common/system/tray/tray_background_view.h",
@@ skipping 447 matching lines @@
   configs += [ "//build/config:precompiled_headers" ]
   defines = [ "ASH_IMPLEMENTATION" ]
 
   public_deps = [
     "//ash/common/strings",
     "//ash/resources",
     "//ash/resources/vector_icons",
   ]
   deps = [
     "//ash/autoclick/common:autoclick",
+    # TODO: Why does this cause a cycle? ugh, typemap for shelf item types
+    "//ash/public/interfaces",
     "//ash/touch_hud",
     "//base",
     "//base:i18n",
     "//base/third_party/dynamic_annotations",
     "//cc",
     "//components/device_event_log",
     "//components/onc",
     "//components/signin/core/account_id",
     "//components/user_manager",
     "//components/wallpaper",
     "//media",
     "//net",
+    # TODO: public_deps?
+    "//services/shell/public/cpp",
     "//skia",
     "//third_party/icu",
     "//ui/accessibility",
     "//ui/app_list/presenter",
     "//ui/aura",
     "//ui/base",
     "//ui/base:ui_data_pack",
     "//ui/base/ime",
     "//ui/compositor",
     "//ui/display",
@@ skipping 824 matching lines @@
   if (is_win) {
     configs -= [ "//build/config/win:console" ]
     configs += [ "//build/config/win:windowed" ]
     deps += [ "//sandbox" ]
   }
 
   if (is_chromeos) {
     deps += [ "//device/bluetooth" ]
   }
 }