Always clobber the out dir on the arm board

tools/bots/cross-vm.py

 #!/usr/bin/python
 # Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
 # for details. All rights reserved. Use of this source code is governed by a
 # BSD-style license that can be found in the LICENSE file.
 
 import os
 import re
 import sys
 
 import bot
@@ skipping 73 matching lines @@
 
     with bot.BuildStep('execute tests'):
       run(test_args)
 
     with bot.BuildStep('execute checked_tests'):
       run(test_args + ['--checked', '--append_logs'])
   finally:
     for path in temporary_files:
       if os.path.exists(path):
         os.remove(path)
+    # We alwasy clobber this to save disk on the arm board.

[Bill Hesse, 2014/06/24 10:33:02]

always

+    bot.Clobber(force=True)
 
 def main():
   name, is_buildbot = bot.GetBotName()
 
   cross_vm_pattern_match = re.match(CROSS_VM, name)
   target_vm_pattern_match = re.match(TARGET_VM, name)
   if cross_vm_pattern_match:
     arch = cross_vm_pattern_match.group(1)
     mode = cross_vm_pattern_match.group(2)
     cross_compiling_builder(arch, mode)
   elif target_vm_pattern_match:
     arch = target_vm_pattern_match.group(1)
     mode = target_vm_pattern_match.group(2)
     target_builder(arch, mode)
   else:
     raise Exception("Unknown builder name %s" % name)
 
 if __name__ == '__main__':
   try:
     sys.exit(main())
   except OSError as e:
     sys.exit(e.errno)