Update existing uses of /wd4267 to use the GN config

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")
 
 gypi_values = exec_script("//build/gypi_to_gn.py",
                           [ rebase_path("ash.gyp") ],
@@ skipping 44 matching lines @@
     "//url",
   ]
 
   if (is_win) {
     sources -= [
       "sticky_keys/sticky_keys_controller.cc",
       "sticky_keys/sticky_keys_controller.h",
     ]
 
     # TODO(jschuh): crbug.com/167187 fix size_t to int truncations.
-    cflags = [ "/wd4267" ]
+    configs += [ "//build/config/compiler:no_size_t_to_int_warning" ]
   }
 
   if (use_x11) {
     configs += [
       "//build/config/linux:x11",
       "//build/config/linux:xfixes",
     ]
     deps += [
       "//ui/events/platform",
       "//ui/gfx/x",
@@ skipping 231 matching lines @@
       "sticky_keys/sticky_keys_overlay_unittest.cc",
       "system/tray/media_security/multi_profile_media_tray_item_unittest.cc",
       "virtual_keyboard_controller_unittest.cc",
       "wm/workspace/workspace_window_resizer_unittest.cc",
     ]
     sources += [
       #'<(SHARED_INTERMEDIATE_DIR)/ui/resources/ui_unscaled_resources.rc',  TODO(GYP)
     ]
   }
 
-  if (is_win) {
-    cflags = [ "/wd4267" ]
-  }
+  configs += [ "//build/config/compiler:no_size_t_to_int_warning" ]
 
   if (!use_x11) {
     sources -= [ "host/ash_window_tree_host_x11_unittest.cc" ]
   }
   if (is_chromeos) {
     sources += [ "first_run/first_run_helper_unittest.cc" ]
     deps += [
       "//device/bluetooth",
       "//ui/display",
       "//ui/display:test_util",
@@ skipping 61 matching lines @@
       "//skia",
       "//testing/gtest",
       "//ui/accessibility",
     ]
 
     if (is_chromeos) {
       deps += [ "//ui/display" ]
     }
   }
 }