Cleanup: Presubmit API is built into depot_tools.

ui/events/PRESUBMIT.py

 # Copyright 2014 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.
 
 """Chromium presubmit script for src/ui/events
 
 See http://dev.chromium.org/developers/how-tos/depottools/presubmit-scripts
-for more details on the presubmit API built into gcl.
+for more details on the presubmit API built into depot_tools.
 """
 
 def GetPreferredTryMasters(project, change):
   return {
     'tryserver.chromium.linux': {
       'linux_chromium_chromeos_rel_ng': set(['defaulttests']),
       'linux_chromium_chromeos_asan_rel_ng': set(['defaulttests']),
     },
     'tryserver.chromium.win': {
       'win_chromium_compile_dbg': set(['defaulttests']),
     }
   }