Remove unused imports in webkitpy with using autoflake.

third_party/WebKit/Tools/Scripts/webkitpy/style/checkers/test_expectations.py

 # Copyright (C) 2010 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 11 matching lines @@
 # SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 # LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 # DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 # THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 # (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
 """Checks WebKit style for test_expectations files."""
 
 import logging
-import optparse
-import os
-import re
-import sys
 
 from common import TabChecker
 from webkitpy.common.host import Host
 from webkitpy.layout_tests.models.test_expectations import TestExpectationParser
 
 
 _log = logging.getLogger(__name__)
 
 
 class TestExpectationsChecker(object):
@@ skipping 31 matching lines @@
     def check_tabs(self, lines):
         self._tab_checker.check(lines)
 
     def check(self, lines):
         expectations = '\n'.join(lines)
         if self._port_obj:
             self.check_test_expectations(expectations_str=expectations, tests=None)
 
         # Warn tabs in lines as well
         self.check_tabs(lines)