Use mojo Shelf 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 134 matching lines @@
     "common/shelf/shelf_alignment_menu.h",
     "common/shelf/shelf_background_animator.cc",
     "common/shelf/shelf_background_animator.h",
     "common/shelf/shelf_background_animator_observer.h",
     "common/shelf/shelf_button.cc",
     "common/shelf/shelf_button.h",
     "common/shelf/shelf_button_pressed_metric_tracker.cc",
     "common/shelf/shelf_button_pressed_metric_tracker.h",
     "common/shelf/shelf_constants.cc",
     "common/shelf/shelf_constants.h",
+    "common/shelf/shelf_controller.cc",
+    "common/shelf/shelf_controller.h",
     "common/shelf/shelf_delegate.h",
     "common/shelf/shelf_item_delegate.h",
     "common/shelf/shelf_item_types.cc",
     "common/shelf/shelf_item_types.h",
     "common/shelf/shelf_layout_manager.cc",
     "common/shelf/shelf_layout_manager.h",
     "common/shelf/shelf_layout_manager_observer.h",
     "common/shelf/shelf_locking_manager.cc",
     "common/shelf/shelf_locking_manager.h",
     "common/shelf/shelf_menu_model.h",
@@ skipping 1523 matching lines @@
   if (is_win) {
     configs -= [ "//build/config/win:console" ]
     configs += [ "//build/config/win:windowed" ]
     deps += [ "//sandbox" ]
   }
 
   if (is_chromeos) {
     deps += [ "//device/bluetooth" ]
   }
 }