Update existing uses of /wd4267 to use the GN config

components/packed_ct_ev_whitelist/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.
 
 static_library("packed_ct_ev_whitelist") {
   sources = [
     "bit_stream_reader.cc",
     "bit_stream_reader.h",
     "packed_ct_ev_whitelist.cc",
     "packed_ct_ev_whitelist.h",
   ]
 
+  configs += [ "//build/config/compiler:no_size_t_to_int_warning" ]
+
   deps = [
     "//base",
     "//content",
     "//net",
   ]
-
-  if (is_win) {
-    # TODO(jschuh): crbug.com/167187 fix size_t to int truncations.
-    cflags = [ "/wd4267" ]
-  }
 }
 
 source_set("unit_tests") {
   testonly = true
   sources = [
     "bit_stream_reader_unittest.cc",
     "packed_ct_ev_whitelist_unittest.cc",
   ]
 
   deps = [
     ":packed_ct_ev_whitelist",
     "//testing/gtest",
   ]
 }