Remove all traces of deprecated Get/SetReleaseTrack calls.

chrome/test/functional/PYAUTO_TESTS

 # Copyright 2013 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 205 matching lines @@
     'chromeos': [
       'chromeos_basic',
       'chromeos_browser',
       'chromeos_crosh',
       'chromeos_file_browser',
       'chromeos_offline',
       'chromeos_power',
       'chromeos_prefs',
       'chromeos_security',
       'chromeos_time',
-      'chromeos_update',
       'chromeos_wifi_sanity',
       'doc_viewing',
       'secure_shell',
       'youtube',
 
       # ===========================
       # Permanently-disabled tests.
       # ===========================
       # No codesign verification on ChromeOS.
       '-codesign',
@@ skipping 339 matching lines @@
       '-search_engines.SearchEnginesTest.testDiscoverSearchEngine',
       '-ntp.NTPTest.testUninstallApp',
       '-ntp.NTPTest.testLaunchAppWithDefaultSettings',
       '-ntp.NTPTest.testLaunchAppRegularTab',
       '-ntp.NTPTest.testLaunchAppPinnedTab',
       '-ntp.NTPTest.testGetAppsWhenInstallApp',
       '-ntp.NTPTest.testLaunchAppNewWindow',
     ],
   },
 }