Update from https://crrev.com/303153

base/BUILD.gn

 # Copyright (c) 2013 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")
 
 if (is_android) {
   import("//build/config/android/rules.gni")
 }
 
@@ skipping 840 matching lines @@
     sources -= [
       "event_recorder_stubs.cc",
       "message_loop/message_pump_libevent.cc",
       "strings/string16.cc",
       # Not using sha1_win.cc because it may have caused a
       # regression to page cycler moz.
       "sha1_win.cc",
     ]
 
     # TODO(jschuh): crbug.com/167187 fix size_t to int truncations.
-    cflags = [ "/wd4267" ]
+    #cflags = [ "/wd4267" ]
 
     libs = [
       "cfgmgr32.lib",
       "netapi32.lib",
       "powrprof.lib",
       "setupapi.lib",
     ]
     ldflags = [
       "/DELAYLOAD:cfgmgr32.dll",
       "/DELAYLOAD:powrprof.dll",
@@ skipping 628 matching lines @@
   # GYP: //base.gyp:base_unittests_apk
   unittest_apk("base_unittests_apk") {
     deps = [
       ":base_java",
       ":base_java_unittest_support",
       ":base_unittests",
     ]
     unittests_dep = ":base_unittests"
   }
 }