Remove ignored bot_update "force" parameter.

scripts/slave/recipes/nacl_ports.py

 # Copyright 2015 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.
 
 DEPS = [
   'chromium',
   'depot_tools/bot_update',
   'depot_tools/gclient',
   'recipe_engine/path',
   'recipe_engine/platform',
   'recipe_engine/properties',
   'recipe_engine/python',
   'recipe_engine/step',
 ]
 
 
 def _CheckoutSteps(api):
   api.gclient.set_config('webports')
-  result = api.bot_update.ensure_checkout(force=True)
+  result = api.bot_update.ensure_checkout()
   api.gclient.runhooks()
   # HACK(aneeshm): Borrowed from iannucci's hack in nacl.py.
   got_revision = result.presentation.properties['got_revision']
   return got_revision
 
 def _AnnotatedStepsSteps(api, got_revision):
   # Default environemnt; required by all builders.
   env = {
       'BUILDBOT_MASTERNAME': api.properties['mastername'],
       'BUILDBOT_BUILDERNAME': api.properties['buildername'],
@@ skipping 15 matching lines @@
   _AnnotatedStepsSteps(api, got_revision)
 
 def GenTests(api):
   yield api.test('linux') +\
     api.platform('linux', 64) +\
     api.properties(mastername = 'client.nacl.ports') +\
     api.properties(buildername = 'linux-glibc-0') +\
     api.properties(revision = 'abcd') +\
     api.properties(slavename = 'TestSlave') +\
     api.properties(slavetype = 'BuilderTester')