Make blink_trybot recipe work on windows

scripts/tools/run_recipe.py

-#!/usr/bin/env python
+#!/usr/bin/env python -u
 # Copyright (c) 2013 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.
 
 """This allows easy execution of a recipe (scripts/slave/recipes, etc.)
 without buildbot.
 
 This is currently useful for testing recipes locally while developing them.
 
 Example:
@@ skipping 74 matching lines @@
 def main(argv):
   fp, bp = parse_args(argv)
 
   if not os.path.exists(SLAVE_DIR):
     os.makedirs(SLAVE_DIR)
 
   env = os.environ.copy()
   env['RUN_SLAVE_UPDATED_SCRIPTS'] = '1'
   env['PYTHONUNBUFFERED'] = '1'
   return subprocess.call(
-      ['python', RUNIT, 'python', ANNOTATED_RUN,
+      ['python', '-u', RUNIT, 'python', '-u', ANNOTATED_RUN,
        '--keep-stdin',  # so that pdb works for local execution
        '--factory-properties', json.dumps(fp),
        '--build-properties',   json.dumps(bp)],
       cwd=SLAVE_DIR,
       env=env)
 
 
 if __name__ == '__main__':
   sys.exit(main(sys.argv))