Fix 'gn check' errors in //ui/* targets.

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",
@@ skipping 225 matching lines @@
   deps = [
     ":app_list",
     ":test_support",
     "//base",
     "//base/test:test_support",
     "//skia",
     "//testing/gtest",
     "//ui/base",
     "//ui/compositor",
     "//ui/events",
+    "//ui/events:test_support",
     "//ui/gl",
     "//ui/resources",
     "//ui/resources:ui_test_pak",
   ]
 
   if (toolkit_views) {
     sources += [
       "views/app_list_main_view_unittest.cc",
       "views/app_list_view_unittest.cc",
       "views/apps_grid_view_unittest.cc",
@@ skipping 16 matching lines @@
       "cocoa/app_list_view_controller_unittest.mm",
       "cocoa/app_list_window_controller_unittest.mm",
       "cocoa/apps_grid_controller_unittest.mm",
       "cocoa/apps_search_box_controller_unittest.mm",
       "cocoa/apps_search_results_controller_unittest.mm",
       "cocoa/test/apps_grid_controller_test_helper.h",
       "cocoa/test/apps_grid_controller_test_helper.mm",
     ]
   }
 }