Make backward-forward compatible version.

appengine/swarming/server/task_queues_test.py

 #!/usr/bin/env python
 # Copyright 2017 The LUCI Authors. All rights reserved.
 # Use of this source code is governed under the Apache License, Version 2.0
 # that can be found in the LICENSE file.
 
 import datetime
 import hashlib
 import logging
 import os
 import sys
@@ skipping 38 matching lines @@
     'dimensions': {
       u'cpu': u'x86-64',
       u'os': u'Ubuntu-16.04',
       u'pool': u'default',
     },
     'env': {},
     'execution_timeout_secs': 24*60*60,
     'io_timeout_secs': None,
   }
   props.update(properties or {})
+  props['dimensions_dict'] = props.pop('dimensions')
   now = utils.utcnow()
   args = {
     'created_ts': now,
     'name': 'Request name',
     'priority': 50,
     'properties': task_request.TaskProperties(**props),
     'expiration_ts': now + datetime.timedelta(seconds=60),
     'tags': [u'tag:1'],
     'user': 'Jesus',
   }
@@ skipping 253 matching lines @@
     self.assert_count(0, task_queues.TaskDimensions)
     self.assertEqual([], task_queues.get_queues(u'bot1'))
 
 
 if __name__ == '__main__':
   if '-v' in sys.argv:
     unittest.TestCase.maxDiff = None
   logging.basicConfig(
       level=logging.DEBUG if '-v' in sys.argv else logging.ERROR)
   unittest.main()