Add config for Chromium Mac 10.11 Force Mac Toolchain

masters/master.chromium.fyi/slaves.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.
 
 # See master.experimental/slaves.cfg for documentation.
 
 
@@ skipping 338 matching lines @@
   {
     'master': 'ChromiumFYI',
     'hostname': 'build155-m1',
     'builder': ['Chromium Mac 10.11'],
     'os': 'mac',
     'version': '10.11',
     'bits': '64',
   },
   {
     'master': 'ChromiumFYI',
+    'hostname': 'build9-m1',
+    'builder': ['Chromium Mac 10.11 Force Mac Toolchain'],
+    'os': 'mac',
+    'version': '10.11',
+    'bits': '64',
+  },
+  {
+    'master': 'ChromiumFYI',
     'hostname': 'vm800-m1',
     'builder': ['Windows 8 App Certification'],
     'os': 'win',
     'version': 'win8',
     'bits': '64',
   },
   {
     'master': 'ChromiumFYI',
     'hostname': 'vm803-m1',
     'builder': ['Linux ARM'],
@@ skipping 405 matching lines @@
   },
   {
     'master': 'ChromiumFYI',
     'builder': 'MD Top Chrome Linux material',
     'hostname': 'slave69-c1',
     'os': 'linux',
     'version': 'trusty',
     'bits': '64',
   },
 ]