Fix various flags in the Win64 GN build

rlz/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.
 
 # Note that this build file assumes rlz_use_chrome_net which is a condition in
 # the GYP file, but is always true for Chrome builds.
 
 config("rlz_config") {
   defines = [ "RLZ_NETWORK_IMPLEMENTATION_CHROME_NET" ]
 }
@@ skipping 96 matching lines @@
   deps = [
     ":rlz_lib",
     ":test_support",
     "//base",
     "//base:prefs",
     "//net:test_support",
     "//testing/gmock",
     "//testing/gtest",
     "//third_party/zlib",
   ]
+
+  if (is_win) {
+    # TODO(jschuh): crbug.com/167187 fix size_t to int truncations.
+    cflags = [ "/wd4267" ]
+  }
 }
 
 executable("rlz_id") {
   sources = [
     "examples/rlz_id.cc",
   ]
   deps = [
     ":rlz_lib",
   ]
 }
 
 if (is_win) {
   shared_library("rlz") {
     sources = [
       "win/dll/dll_main.cc",
       "win/dll/exports.cc",
     ]
     deps = [
       ":rlz_lib",
       "//third_party/zlib",
     ]
   }
 }