Allow pyauto performance tests in perf.py to run as an autotest.

chrome/test/functional/PYAUTO_TESTS

 # Copyright (c) 2011 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.
 #
 # This file lists the pyauto tests that run as a part of the functional test
 # suite.
 #
 # Tests can be enabled on a per-platform basis. Tests not listed here will
 # not be run.
 #
@@ skipping 445 matching lines @@
     ],
   },
 
   # ChromeOS login tests.
   'CHROMEOS_LOGIN': {
     'chromeos': [
       'chromeos_login',
     ],
   },
 
+  # ChromeOS performance tests.
+  'CHROMEOS_PERF': {
+    'chromeos': [
+      'perf',
+    ],
+  },
+
   # HTML5 media performance tests.
   'AV_PERF': {
      'linux': [
        'media.media_playbacktime',
        'media.media_perf',
        'media.media_fps',
      ],
   },
 
   # HTML5 media functional tests.
   'AV_FUNC': {
      'linux': [
        'media.media_event_simple_action',
        'media.media_event_simple_test',
        'media.media_event_track',
      ],
   },
 }