[Predator] Run predator.

appengine/findit/util_scripts/local_cache.py

 # Copyright 2016 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.
 
 import logging
 import os
 import pickle
 import threading
 import zlib
 
@@ skipping 15 matching lines @@
   def Get(self, key):
     with LocalCacher.lock:
       path = os.path.join(self.cache_dir, key)
       if not os.path.exists(path):
         return None
 
       try:
         with open(path) as f:
           return pickle.loads(zlib.decompress(f.read()))
       except Exception as error:  # pragma: no cover.
-        logging.exception('Failed loading cache: %s', error)
-        return None
+        raise Exception('Failed loading cache: %s' % error)
 
   def Set(self, key, data, expire_time=0):  # pylint: disable=W
     with LocalCacher.lock:
       try:
         with open(os.path.join(self.cache_dir, key), 'wb') as f:
           f.write(zlib.compress(pickle.dumps(data)))
       except Exception as e:  # pragma: no cover.
-        logging.exception('Failed setting cache for key %s: %s', key, e)
+        raise Exception('Failed setting cache for key %s: %s' % (key, e))