Add attempt to update remote and rebase before pushing

cros_mark_as_stable.py

 #!/usr/bin/python
 
 # Copyright (c) 2010 The Chromium OS 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 module uprevs a given package's ebuild to the next revision."""
 
 
 import fileinput
@@ skipping 115 matching lines @@
   # TODO(sosa) - Add logic for buildbot to check whether other slaves have
   # completed and push this change only if they have.
 
   # Sanity check to make sure we're on a stabilizing branch before pushing.
   if not _CheckOnStabilizingBranch():
     generate_test_report.Die('Expected %s to be on branch "%s"' %
                              (_CHROMIUMOS_OVERLAYS_DIRECTORY,
                               _STABLE_BRANCH_NAME))
   _RunCommand('git cl upload --desc_from_logs -m "%s"' %
     'Marking set of ebuilds as stable')
+  _RunCommand('git remote update')
+  _RunCommand('git rebase origin/master')
   _RunCommand('git cl push %s' % gflags.FLAGS.push_options)
 
 
 def _RunCommand(command):
   """Runs a shell command and returns stdout back to caller."""
   _Print('  + %s' % command)
   proc_handle = subprocess.Popen(command, stdout=subprocess.PIPE, shell=True)
   return proc_handle.communicate()[0]
 
 
@@ skipping 212 matching lines @@
              'and reset the git repo yourself.' %
              (package_list[:index], _CHROMIUMOS_OVERLAYS_DIRECTORY))
       raise e
   elif command == 'push':
     _PushChange()
 
 
 if __name__ == '__main__':
   main(sys.argv)