swarming: fix support for raw command + isolated file

appengine/swarming/swarming_bot/bot_code/task_runner.py

 # Copyright 2013 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.
 
 """Runs a Swarming task.
 
 Downloads all the necessary files to run the task, executes the command and
 streams results back to the Swarming server.
 
 The process exit code is 0 when the task was executed, even if the task itself
@@ skipping 67 matching lines @@
   """Returns the path to itself to run run_isolated.
 
   Mocked in test to point to the real run_isolated.py script.
   """
   return [sys.executable, THIS_FILE, 'run_isolated']
 
 
 def get_isolated_args(is_grpc, work_dir, task_details, isolated_result,
                       bot_file, run_isolated_flags):
   """Returns the command to call run_isolated. Mocked in tests."""
-  assert (bool(task_details.command) !=
-          bool(task_details.isolated and task_details.isolated.get('input')))
   bot_dir = os.path.dirname(work_dir)
   if os.path.isfile(isolated_result):
     os.remove(isolated_result)
   cmd = []
 
   # Isolated options.
   if task_details.isolated:
     cmd.extend(
         [
           '-I', task_details.isolated['server'].encode('utf-8'),
@@ skipping 574 matching lines @@
     options.start = now
 
   try:
     load_and_run(
         options.in_file, options.swarming_server, options.is_grpc,
         options.cost_usd_hour, options.start, options.out_file,
         args, options.bot_file, options.auth_params_file)
     return 0
   finally:
     logging.info('quitting')