[Bindings] Create and use V8 context snapshots

build/config/features.gni

 # 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.
 
 # =============================================
 #   PLEASE DO NOT ADD MORE FLAGS TO THIS FILE
 # =============================================
 #
 # These flags are effectively global. Your feature flag should go near the
 # code it controls. Most of these items are here now because they control
@@ skipping 44 matching lines @@
   # Note: this setting is ignored if is_chrome_branded.
   fieldtrial_testing_like_official_build = is_chrome_branded
 
   # libudev usage. This currently only affects the content layer.
   use_udev = is_linux && !is_chromecast
 
   use_dbus = is_linux && !is_chromecast
 
   # Option controlling the use of GConf (the classic GNOME configuration
   # system).
-  use_gconf = is_linux && !is_chromeos && !is_chromecast
+  use_gconf = is_linux && !is_chromeos && !is_chromecast &&
+              current_toolchain == default_toolchain
 
   use_gio = is_linux && !is_chromeos && !is_chromecast
 }
 #
 # =============================================
 #   PLEASE DO NOT ADD MORE FLAGS TO THIS FILE
 # =============================================
 #
 # See comment at the top.