Delete all references to GIT_MODE=True from build

scripts/slave/recipes/swarming/staging.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.
 
 """Swarming staging recipe: runs tests for HEAD of chromium using HEAD of
 swarming_client toolset on Swarming staging server instances
 (*-dev.appspot.com).
 
 Intended to catch bugs in swarming_client and Swarming servers early on, before
 full roll out.
@@ skipping 48 matching lines @@
     # Only one android bot, bump the expiration higher.
     # TODO(stip/maruel): add default_expiration property to api.swarming? Add
     # expiration to api.swarming.task()?
     api.swarming._default_expiration = 5*60*60
   else:
     api.chromium.set_config(
         'chromium', BUILD_CONFIG=api.properties.get('configuration', 'Release'))
 
   # We are checking out Chromium with swarming_client dep unpinned and pointing
   # to ToT of swarming_client repo, see recipe_modules/gclient/config.py.
-  api.gclient.set_config('chromium', GIT_MODE=True)
+  api.gclient.set_config('chromium')
   if api.properties.get('platform') == 'android':
     api.gclient.apply_config('android')
   api.gclient.c.solutions[0].custom_vars['swarming_revision'] = ''
   api.gclient.c.revisions['src/tools/swarming_client'] = 'HEAD'
 
   # Enable test isolation. Modifies GYP_DEFINES used in 'runhooks' below.
   api.isolate.set_isolate_environment(api.chromium.c)
 
   api.chromium.cleanup_temp()
   # Checkout chromium + deps (including 'master' of swarming_client).
@@ skipping 139 matching lines @@
     api.test('android') +
     api.platform.name('linux') +
     api.properties.scheduled() +
     api.properties(configuration='Release', platform='android') +
     api.override_step_data(
         'isolate tests',
         api.isolate.output_json(targets=[
             'dummy_target_1', 'dummy_target_2', 'chrome_public_test_apk'])
     )
   )