Add support for "additional_mirrors" property in trybot configs.

scripts/slave/recipe_modules/perf_try/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.
 
 """API for the perf try job recipe module.
 
 This API is meant to enable the perf try job recipe on any chromium-supported
 platform for any test that can be run via buildbot, perf or otherwise.
 """
 
@@ skipping 142 matching lines @@
       self.m.gclient.c.revisions['src'] = str(revision)
       update_step = self.m.bot_update.ensure_checkout(
           suffix=str(revision), force=True, patch=False,
           update_presentation=False)
       assert update_step.json.output['did_run']
       self.m.chromium.runhooks(name='runhooks on %s' % str(revision))
 
     return update_step
 
   def _compile(self, name, mastername, buildername, update_step,
-               master_dict, test_spec=None):
+               master_dict, test_specs=None):
     """Runs compile and related steps for given builder."""
-    if test_spec is None:
-      test_spec = {}
+    if test_specs is None:
+      test_specs = [{}]
     compile_targets, _ = self.m.chromium_tests.get_compile_targets_and_tests(
         mastername,
         buildername,
-        master_dict,
-        test_spec,
+        [master_dict],
+        None,
+        test_specs,
         override_bot_type='builder_tester',
         override_tests=[])
     if self.m.chromium.c.TARGET_PLATFORM == 'android':
       self.m.chromium_android.clean_local_files()
       compile_targets = None
     else:
       # Removes any chrome temporary files or build.dead directories.
       self.m.chromium.cleanup_temp()
 
     if 'With Patch' in name:
@@ skipping 260 matching lines @@
 
 def _prepend_src_to_path_in_command(test_cfg):
   command_to_run = []
   for v in test_cfg.get('command').split():
     if v in ['./tools/perf/run_benchmark',
              'tools/perf/run_benchmark',
              'tools\\perf\\run_benchmark']:
       v = 'src/tools/perf/run_benchmark'
     command_to_run.append(v)
   test_cfg.update({'command': ' '.join(command_to_run)})