Pyauto tests were failing on coverage bots because of missing comma.

chrome/test/functional/PYAUTO_TESTS

 # 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.
 #
 # 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 837 matching lines @@
       '-apptest',
       '-plugins',
       '-omnibox',
       '-special_tabs',
       '-youtube.YoutubeTest.testPlayerStatus',
       '-translate.TranslateTest.testSeveralLanguages',
       '-translate.TranslateTest.testBarNotVisibleOnSSLErrorPage',
       '-ntp.NTPTest.testLaunchAppFullScreen',
       '-https.SSLTest.testSSLCertOK',
       '-https.SSLTest.testSSLCertAuthorityOK',
-      '-media.media_basic_playback.MediaConstrainedNetworkPerfTest.testBasicPlaybackMatrix'
+      '-media.media_basic_playback.MediaConstrainedNetworkPerfTest.testBasicPlaybackMatrix',
       '-policy_prefs_ui.PolicyPrefsUITest.testNoUserPoliciesNoBanner',
       '-policy_prefs_ui.PolicyPrefsUITest.testToggleUserPolicyTogglesBanner',
     ],
   },
 }