Revert of remote_run: disable canary, all on latest.

scripts/slave/remote_run.py

 #!/usr/bin/env python
 # Copyright 2016 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 argparse
 import copy
 import json
 import logging
 import os
@@ skipping 19 matching lines @@
 
 
 LOGGER = logging.getLogger('remote_run')
 
 
 # CIPD_PINS is a mapping of master name to pinned recipe engine CIPD package
 # version. If no pin is found, the CIPD pin for "None" will be used.
 _CIPD_PINS = {
   # Default recipe engine pin.
   None: 'latest',
+
+  # Custom per-master pins.
+  'chromium.infra': 'canary',
 }
 
 
 def _call(cmd, **kwargs):
   LOGGER.info('Executing command: %s', cmd)
   exit_code = subprocess.call(cmd, **kwargs)
   LOGGER.info('Command %s finished with exit code %d.', cmd, exit_code)
   return exit_code
 
 
@@ skipping 164 matching lines @@
     # Re-execute with the updated remote_run.py.
     return _call([sys.executable] + argv)
 
   stream = annotator.StructuredAnnotationStream()
   with stream.step('remote_run_result'):
     return main(argv)
 
 
 if __name__ == '__main__':
   sys.exit(shell_main(sys.argv))