Make chromium_tests recipe module explicitly set GIT_MODE

scripts/slave/recipe_modules/chromium_tests/api.py

 # 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 collections
 import contextlib
 import copy
 import itertools
 import json
 
@@ skipping 109 matching lines @@
     # not support that.
     self.m.chromium.c.gyp_env.GYP_DEFINES.update(
         bot_config.get('GYP_DEFINES', {}))
     if bot_config.get('use_isolate'):
       self.m.isolate.set_isolate_environment(self.m.chromium.c)
 
     self.m.gclient.set_config(
         bot_config.get('gclient_config'),
         PATCH_PROJECT=self.m.properties.get('patch_project'),
         BUILDSPEC_VERSION=buildspec_version,
+        GIT_MODE=True,
         **bot_config.get('gclient_config_kwargs', {}))
 
     self.m.test_results.set_config(
         bot_config.get('test_results_config'))
 
     if bot_config.get('android_config'):
       self.m.chromium_android.configure_from_properties(
           bot_config.get('android_config'),
           **bot_config.get('chromium_config_kwargs', {}))
 
@@ skipping 867 matching lines @@
     targets in |compile_targets|."""
     result = []
     for test in tests:
       test_compile_targets = test.compile_targets(api)
       # Always return tests that don't require compile. Otherwise we'd never
       # run them.
       if ((set(compile_targets) & set(test_compile_targets)) or
           not test_compile_targets):
         result.append(test)
     return result