Teach `mojo_benchmark` to upload results to perf dashboard.

mojo/devtools/common/devtoolslib/perf_dashboard.py

 # Copyright 2015 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.
 
 # Disable the line-too-long warning.
 # pylint: disable=C0301
 """This module implements the Chromium Performance Dashboard JSON v1.0 data
 format.
 
 See http://www.chromium.org/developers/speed-infra/performance-dashboard/sending-data-to-the-performance-dashboard.
@@ skipping 73 matching lines @@
   dashboard_group.add_argument(
       '--build-number', type=int,
       help='Build number, used to construct link to buildbot log by the '
            'dashboard.')
   dashboard_group.add_argument(
       '--dry-run', action='store_true', default=False,
       help='Display the server URL and the data to upload, but do not actually '
            'upload the data.')
 
 
+def normalize_label(label):
+  """Normalizes a label to be used for data sent to performance dashboard.
+
+  This replaces:
+    '/' -> '-', as slashes are used to denote test/sub-test relation.
+    ' ' -> '_', as there is a convention of not using spaces in test names.
+
+  Returns:
+    Normalized label.
+  """
+  return label.replace('/', '-').replace(' ', '_')
+
+
 def _get_commit_count():
   """Returns the number of git commits in the repository of the cwd."""
   return subprocess.check_output(
       ["git", "rev-list", "HEAD", "--count"]).strip()
 
 
 def _get_current_commit():
   """Returns the hash of the current commit in the repository of the cwd."""
   return subprocess.check_output(["git", "rev-parse", "HEAD"]).strip()
 
@@ skipping 79 matching lines @@
 
     dashboard_params = urllib.urlencode({
         "masters": master_name,
         "bots": bot_name,
         "tests": test_name,
         "rev": point_id
     })
     print "Results Dashboard: %s/report?%s" % (upload_url, dashboard_params)
 
   return True