Remove thirdparty/unittest2 from webkitpy and require python2.7.

Tools/Scripts/webkitpy/style/checkers/cpp_unittest.py

 # -*- coding: utf-8; -*-
 #
 # Copyright (C) 2011 Google Inc. All rights reserved.
 # Copyright (C) 2009 Torch Mobile Inc.
 # Copyright (C) 2009 Apple Inc. All rights reserved.
 # Copyright (C) 2010 Chris Jerdonek (cjerdonek@webkit.org)
 #
 # Redistribution and use in source and binary forms, with or without
 # modification, are permitted provided that the following conditions are
 # met:
@@ skipping 20 matching lines @@
 # (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
 """Unit test for cpp_style.py."""
 
 # FIXME: Add a good test that tests UpdateIncludeState.
 
 import os
 import random
 import re
-import webkitpy.thirdparty.unittest2 as unittest
+import unittest
+
 import cpp as cpp_style
 from cpp import CppChecker
 from ..filter import FilterConfiguration
 from webkitpy.common.system.filesystem import FileSystem
 
 # This class works as an error collector and replaces cpp_style.Error
 # function for the unit tests.  We also verify each category we see
 # is in STYLE_CATEGORIES, to help keep that list up to date.
 class ErrorCollector:
     _all_style_categories = CppChecker.categories
@@ skipping 5153 matching lines @@
     def test_ne(self):
         """Test __ne__ inequality function."""
         checker1 = self._checker()
         checker2 = self._checker()
 
         # != calls __ne__.
         # By default, __ne__ always returns true on different objects.
         # Thus, just check the distinguishing case to verify that the
         # code defines __ne__.
         self.assertFalse(checker1 != checker2)