Adding variable buillder for builders using win_gn folder

masters/master.tryserver.chromium.win/master.cfg

 # -*- python -*-
 # ex: set syntax=python:
 # Copyright (c) 2012 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.
 
 # READ THIS:
 # See http://dev.chromium.org/developers/testing/chromium-build-infrastructure
 
 import os
@@ skipping 193 matching lines @@
 }
 
 # These variable builders are used by Findit to identify culprit commits for
 # compile or test failures on the main waterfall. They run on optional slaves
 # and NOT CQ slaves.
 variable_builders = [
   {
     'name': 'win_chromium_variable',
     'factory': m_annotator.BaseFactory('findit/chromium/compile'),
     'slavebuilddir': 'win'
-  }
+  },
+  {
+    'name': 'win_chromium_variable_gn',
+    'factory': m_annotator.BaseFactory('findit/chromium/compile'),
+    'slavebuilddir': 'win_gn'
+  },
 ]
 
 c['builders'] = [
   b_win_nacl_sdk,
   b_win_nacl_sdk_build,
 ] + chromium_builders + variable_builders
 
 
 # Slaves are loaded from slaves.cfg.
 slaves = slaves_list.SlavesList('slaves.cfg', 'TryServerChromiumWin')
@@ skipping 123 matching lines @@
 #  base.make_stop_form = hack_stop(base.make_stop_form)
 
 
 ####### PROJECT IDENTITY
 
 # The 'projectURL' string will be used to provide a link
 # from buildbot HTML pages to your project's home page.
 c['projectURL'] = 'http://dev.chromium.org/developers/testing/try-server-usage'
 
 # vi: set ts=4 sts=2 sw=2 et: