Update existing uses of /wd4267 to use the GN config

components/keyed_service/content/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.
 
 assert(!is_ios)
 
 component("content") {
   output_name = "keyed_service_content"
   sources = [
     "browser_context_dependency_manager.cc",
     "browser_context_dependency_manager.h",
     "browser_context_keyed_base_factory.cc",
     "browser_context_keyed_base_factory.h",
     "browser_context_keyed_service_factory.cc",
     "browser_context_keyed_service_factory.h",
     "browser_context_keyed_service_shutdown_notifier_factory.cc",
     "browser_context_keyed_service_shutdown_notifier_factory.h",
     "refcounted_browser_context_keyed_service_factory.cc",
     "refcounted_browser_context_keyed_service_factory.h",
   ]
 
+  # TODO(jschuh): crbug.com/167187 fix size_t to int truncations.
+  configs += [ "//build/config/compiler:no_size_t_to_int_warning" ]
+
   defines = [ "KEYED_SERVICE_IMPLEMENTATION" ]
-  if (is_win) {
-    # TODO(jschuh): crbug.com/167187 fix size_t to int truncations.
-    cflags = [ "/wd4267" ]
-  }
 
   deps = [
     "//base",
     "//base:prefs",
     "//base/third_party/dynamic_annotations",
     "//content/public/common",
     "//components/keyed_service/core",
     "//components/user_prefs",
   ]
 }