Stop setting use_qualified_include to true now that that is the default.

ios/chrome/today_extension/strings/BUILD.gn

 # Copyright 2016 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/locales.gni")
 import("//tools/grit/grit_rule.gni")
 
 grit("strings") {
   source = "ios_today_extension_strings.grd"
   output_dir = "$root_gen_dir/ios/today_extension"
-  use_qualified_include = true
   outputs = [
     "grit/ios_today_extension_strings.h",
   ]
   foreach(locale, locales_with_fake_bidi) {
     outputs += [ "ios_today_extension_strings_$locale.pak" ]
   }
 }