Pass mb_mastername and mb_buildername as parameters to override the default.

scripts/slave/recipe_modules/ios/api.py

 # Copyright 2015 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 copy
 
 from recipe_engine import recipe_api
 
 
 class iOSApi(recipe_api.RecipeApi):
@@ skipping 295 matching lines @@
       # The same test may be configured to run on multiple simulators.
       # Only specify each test once for the analyzer.
       tests = list(set(test['app'] for test in self.__config['tests']))
 
       test_targets, compile_targets = (
         self.m.chromium_tests.analyze(
           affected_files,
           tests,
           self.__config['additional_compile_targets'] + tests,
           'trybot_analyze_config.json',
+          self.m.properties['mastername'],
+          self.m.properties['buildername'],
           additional_names=['chromium', 'ios']
         )
       )
 
       test_targets = set(test_targets)
 
       for test in self.__config['tests']:
         if test['app'] not in test_targets:
           test['skip'] = True
 
@@ skipping 147 matching lines @@
         self.configuration,
         'iossim',
       ),
       'ninja': self.m.path.join(
         'src',
          build_dir,
          '%s-%s' % (self.configuration, platform),
          'iossim',
       ),
     }[self.compiler]