libyuv: Add GCC trybot.

masters/master.client.libyuv/slaves.cfg

 # 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.
 
 slaves = [
   # Linux 32-bit.
   {
     'master': 'Libyuv',
     'os': 'linux',
     'version': 'precise',
     'bits': '32',
     'builder': [
       'Linux32 Debug',
       'Linux32 Release',
     ],
     'hostname': 'vm321-m3',
   }
 ] + [
   # Linux 64-bit.
   {
     'master': 'Libyuv',
     'os': 'linux',
     'version': 'precise',
     'bits': '64',
     'builder': [
       'Linux64 Debug',
       'Linux64 Release',
       'Linux64 Debug (GN)',
       'Linux64 Release (GN)',
+      # TODO(kjellander): Add when trybot is green (crbug.com/625889).
+      #'Linux GCC',
       'Linux Asan',
       'Linux Memcheck',
       'Linux MSan',
       'Linux Tsan v2',
       'Linux UBSan',
       'Linux UBSan vptr',
       'Android Debug',
       'Android Release',
       'Android Debug (GN)',
       'Android Release (GN)',
@@ skipping 48 matching lines @@
       'Win32 Debug (Clang)',
       'Win32 Release (Clang)',
       'Win64 Debug (Clang)',
       'Win64 Release (Clang)',
       'Win64 Debug (GN)',
       'Win64 Release (GN)',
     ],
     'hostname': 'vm%d-m3' % i,
   } for i in [32, 324]
 ]