Add UMA to hotword trigger extension.

tools/metrics/actions/extract_actions.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.
 
 """Extract UserMetrics "actions" strings from the Chrome source.
 
 This program generates the list of known actions we expect to see in the
 user behavior logs.  It walks the Chrome source, looking for calls to
@@ skipping 389 matching lines @@
 
   # Actions sent by Chrome Connectivity Diagnostics.
   actions.add('ConnectivityDiagnostics.LaunchSource.OfflineChromeOS')
   actions.add('ConnectivityDiagnostics.LaunchSource.WebStore')
   actions.add('ConnectivityDiagnostics.UA.LogsShown')
   actions.add('ConnectivityDiagnostics.UA.PassingTestsShown')
   actions.add('ConnectivityDiagnostics.UA.SettingsShown')
   actions.add('ConnectivityDiagnostics.UA.TestResultExpanded')
   actions.add('ConnectivityDiagnostics.UA.TestSuiteRun')
 
+  # Actions sent by 'Ok Google' Hotwording.
+  actions.add('Hotword.HotwordTrigger')
+
 def GrepForActions(path, actions):
   """Grep a source file for calls to UserMetrics functions.
 
   Arguments:
     path: path to the file
     actions: set of actions to add to
   """
   global number_of_files_total
   number_of_files_total = number_of_files_total + 1
   # we look for the UserMetricsAction structure constructor
@@ skipping 403 matching lines @@
 
   with open(actions_xml_path, 'wb') as f:
     f.write(pretty)
   print ('Updated %s. Don\'t forget to add it to your changelist' %
          actions_xml_path)
   return 0
 
 
 if '__main__' == __name__:
   sys.exit(main(sys.argv))