Make bisection recipes explicitly set GIT_MODE

scripts/slave/recipes/bisection/android_bisect.py

 # Copyright (c) 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.
 
 from recipe_engine.types import freeze
 
 DEPS = [
     'auto_bisect',
     'bisect_tester',
     'depot_tools/bot_update',
@@ skipping 82 matching lines @@
       'REPO_NAME': 'src',
       'REPO_URL': REPO_URL,
       'INTERNAL': False,
       'BUILD_CONFIG': 'Release',
       'TARGET_PLATFORM': 'android',
   }
   kwargs.update(bot_config.get('kwargs', {}))
   api.chromium_android.configure_from_properties(recipe_config, **kwargs)
   api.chromium.set_config(recipe_config, **kwargs)
   api.chromium_android.c.set_val({'deps_file': 'DEPS'})
-  api.gclient.set_config('chromium')
+  api.gclient.set_config('chromium', GIT_MODE=True)
   for c in bot_config.get('gclient_apply_config', []):
     api.gclient.apply_config(c)
   update_step = api.auto_bisect.ensure_checkout()
   api.path.c.dynamic_paths['catapult'] = api.m.auto_bisect.working_dir.join(
       'catapult')
   api.chromium_android.clean_local_files()
 
   bot_db = api.chromium_tests.create_bot_db_from_master_dict(mastername,
                                                              master_dict)
 
@@ skipping 578 matching lines @@
     # multiple_device_status
     api.step_data('Debug Info', retcode=1) +
     api.override_step_data('device_status (3)',
         api.json.output(working_device)) +
     api.step_data('Expanding revision range.for revisions %s:%s (2)' % (
             good_revision_hash, bad_revision_hash),
         stdout=api.json.output([[bad_revision_hash, 'ignored'], [
             good_revision_hash, 'ignored']])) +
     api.step_data('Post bisect results',
         stdout=api.json.output({'status_code': 200})))