Update buildbots to parse new telemetry JSON format.

scripts/slave/telemetry.py

 #! /usr/bin/env python
 # Copyright (c) 2012 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.
 
 """Set up and invoke telemetry tests."""
 
 import json
 import optparse
 import os
@@ skipping 59 matching lines @@
 
   test_specification = [test_name]
 
   env = os.environ
 
   # List of command line arguments common to all test platforms.
   common_args = [
       # INFO level verbosity.
       '-v',
       # Output results in the format the buildbot expects.
-      '--output-format=buildbot',
+      '--chartjson',
       ]
 
   if profile_type:
     profile_dir = os.path.join(
         build_dir, target, 'generated_profile', profile_type)
     common_args.append('--profile-dir=' + profile_dir)
   if extra_args:
     common_args.extend(extra_args)
 
   commands = []
@@ skipping 83 matching lines @@
       continue
 
     retval = chromium_utils.RunCommand(command, env=env)
     if retval != 0:
       break
   return retval
 
 
 if '__main__' == __name__:
   sys.exit(main(sys.argv))