Remove all unused variables.

third_party/WebKit/Tools/Scripts/webkitpy/performance_tests/perftestsrunner.py

 # Copyright (C) 2012 Google Inc. All rights reserved.
 #
 # Redistribution and use in source and binary forms, with or without
 # modification, are permitted provided that the following conditions are
 # met:
 #
 #     * Redistributions of source code must retain the above copyright
 # notice, this list of conditions and the following disclaimer.
 #     * Redistributions in binary form must reproduce the above
 # copyright notice, this list of conditions and the following disclaimer
@@ skipping 343 matching lines @@
                 return False
             if parsed_response.get('status') != 'OK':
                 _log.error("Uploaded JSON to %s but got an error:" % url)
                 _log.error(json.dumps(parsed_response, indent=4))
                 return False
 
         _log.info("JSON file uploaded to %s." % url)
         return True
 
     def _run_tests_set(self, tests):
-        result_count = len(tests)
         failures = 0
         self._results = []
 
         for i, test in enumerate(tests):
             _log.info('Running %s (%d of %d)' % (test.test_name(), i + 1, len(tests)))
             start_time = time.time()
             metrics = test.run(self._options.time_out_ms)
             if metrics:
                 self._results.append((test, metrics))
             else:
                 failures += 1
                 _log.error('FAILED')
 
             _log.info('Finished: %f s' % (time.time() - start_time))
             _log.info('')
 
         return failures