Add support for "additional_mirrors" property in trybot configs.

tests/masters_recipes_test.py

 #!/usr/bin/env python
 # 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.
 
 import argparse
 import json
 import os
 import subprocess
 import sys
@@ skipping 69 matching lines @@
     ],
     'master.chromium.memory': [
         'Linux ASan Tests (sandboxed)',
     ],
     'master.chromium.win': [
         'Win x64 Builder (dbg)',
     ],
 }
 
 
+# TODO(kbr): remove these suppressions. They're only needed
+# temporarily during the transition of the chromium.gpu bots to the
+# Chromium recipe, in order to achieve full code coverage while the
+# bots are actually running a different recipe.
+WRONG_RECIPE_SUPPRESSIONS = [
+  'GPU Linux Builder',
+  'Linux Release (NVIDIA)',
+]
+
 def getBuilders(recipe_name):
   """Asks the given recipe to dump its BUILDERS dictionary.
 
   This must be implemented by the recipe in question.
   """
   (fh, builders_file) = tempfile.mkstemp('.json')
   os.close(fh)
   try:
     subprocess.check_call([
         os.path.join(BASE_DIR, 'scripts', 'slave', 'recipes.py'),
@@ skipping 63 matching lines @@
     if recipe_side_builders is not None:
       bogus_builders = set(recipe_side_builders.keys()).difference(
           set(builders.keys()))
       if bogus_builders:
         exit_code = 1
         print 'The following builders from chromium recipe'
         print 'do not exist in master config for %s:' % master
         print '\n'.join('\t%s' % b for b in sorted(bogus_builders))
 
       other_recipe_builders = set(recipe_side_builders.keys()).difference(
-          set(chromium_recipe_builders[master]))
+          set(chromium_recipe_builders[master])).difference(
+            set(WRONG_RECIPE_SUPPRESSIONS))

[Sergey Berezin, 2016/01/06 01:50:56]

nit: 4 space indent for args

       if other_recipe_builders:
         exit_code = 1
         print 'The following builders from chromium recipe'
         print 'are configured to run a different recipe on the master'
         print '(%s):' % master
         print '\n'.join('\t%s' % b for b in sorted(other_recipe_builders))
 
 
   for master in TRYSERVER_MASTERS:
     short_master = master.replace('master.', '')
@@ skipping 54 matching lines @@
     exit_code = 1
     print 'Unused suppressions:'
     print '\n'.join(sorted(
         '\t%s:%s' % (b[0], b[1]) for b in unused_suppressions))
 
   return exit_code
 
 
 if __name__ == '__main__':
   sys.exit(main(sys.argv[1:]))