Remove all mac 10.5 bots from the main waterfall. Create placeholders for 10.7 bots.

masters/master.chromium/master_gatekeeper_cfg.py

 # 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.
 
 from master import gatekeeper
 from master import master_utils
 
 # This is the list of the builder categories and the corresponding critical
 # steps. If one critical step fails, gatekeeper will close the tree
 # automatically.
@@ skipping 34 matching lines @@
   'compile': ['check_deps2git', 'check_deps', 'compile', 'archive_build'],
   # Annotator scripts are triggered as a 'build' step.
   # The gatekeeper currently does not recognize failure in a
   # @@@BUILD_STEP@@@, so we must match on the buildbot-defined step.
   'android': ['build'],
 }
 
 exclusions = {
   # nacl_integration disabled on two Mac bots.
   # http://crbug.com/131422
-  'Mac10.5 Tests (1)': ['nacl_integration'],
-  'Mac 10.5 Tests (dbg)(1)': ['nacl_integration'],
   'Mac10.6 Tests (1)': ['nacl_integration'],
   'Mac 10.6 Tests (dbg)(1)': ['nacl_integration'],
+  #'Mac10.7 Tests (1)': ['nacl_integration'],
+  #'Mac 10.7 Tests (dbg)(1)': ['nacl_integration'],
 }
 
 forgiving_steps = ['update_scripts', 'update', 'svnkill', 'taskkill',
                    'archive_build', 'start_crash_handler']
 
 def Update(config, active_master, c):
   c['status'].append(gatekeeper.GateKeeper(
       fromaddr=active_master.from_address,
       categories_steps=categories_steps,
       exclusions=exclusions,
@@ skipping 13 matching lines @@
       exclusions=exclusions,
       relayhost=config.Master.smtp,
       subject='buildbot %(result)s in %(projectName)s on %(builder)s, '
               'revision %(revision)s',
       sheriffs=None,
       extraRecipients=['nacl-broke@google.com'],
       lookup=master_utils.FilterDomain(),
       forgiving_steps=forgiving_steps,
       tree_status_url=None,
       use_getname=True))