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

Tools/Scripts/webkitpy/layout_tests/views/printing_unittest.py

 # Copyright (C) 2010, 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 10 matching lines @@
 # OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 # 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.
 
 """Unit tests for printing.py."""
 
+import StringIO
 import optparse
-import StringIO
 import sys
 import time
-import webkitpy.thirdparty.unittest2 as unittest
+import unittest
 
 from webkitpy.common.host_mock import MockHost
 
 from webkitpy.common.system import logtesting
 from webkitpy.layout_tests import port
 from webkitpy.layout_tests.controllers import manager
 from webkitpy.layout_tests.models import test_expectations
 from webkitpy.layout_tests.models import test_failures
 from webkitpy.layout_tests.models import test_results
 from webkitpy.layout_tests.views import printing
@@ skipping 197 matching lines @@
         printer.print_finished_test(result, expected=True, exp_str='', got_str='')
 
         printer.print_started_test('passes/text.html')
         result = self.get_result('passes/text.html')
         printer.print_finished_test(result, expected=True, exp_str='', got_str='')
 
         # Only the first test's start should be printed.
         lines = err.buflist
         self.assertEqual(len(lines), 1)
         self.assertTrue(lines[0].endswith('passes/image.html\n'))