Remove more dead app list code.

ui/app_list/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/ui.gni")
 import("//testing/test.gni")
 
 component("app_list") {
   sources = [
     "app_list_constants.cc",
     "app_list_constants.h",
     "app_list_export.h",
     "app_list_folder_item.cc",
     "app_list_folder_item.h",
     "app_list_item.cc",
     "app_list_item.h",
     "app_list_item_list.cc",
     "app_list_item_list.h",
     "app_list_item_list_observer.h",
     "app_list_item_observer.h",
     "app_list_model.cc",
     "app_list_model.h",
     "app_list_model_observer.h",
     "app_list_switches.cc",
     "app_list_switches.h",
-    "app_list_view_delegate.cc",
     "app_list_view_delegate.h",
     "folder_image.cc",
     "folder_image.h",
     "pagination_controller.cc",
     "pagination_controller.h",
     "pagination_model.cc",
     "pagination_model.h",
     "pagination_model_observer.h",
     "search/dictionary_data_store.cc",
     "search/dictionary_data_store.h",
@@ skipping 231 matching lines @@
       "views/speech_view_unittest.cc",
       "views/test/apps_grid_view_test_api.cc",
       "views/test/apps_grid_view_test_api.h",
     ]
     deps += [
       "//ui/views",
       "//ui/views:test_support",
     ]
   }
 }