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

Tools/Scripts/webkitpy/layout_tests/servers/apache_http_unittest.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 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.
 
 import re
 import sys
-import webkitpy.thirdparty.unittest2 as unittest
+import unittest
 
 from webkitpy.common.system.executive_mock import MockExecutive
 from webkitpy.common.system.outputcapture import OutputCapture
 from webkitpy.common.host_mock import MockHost
 from webkitpy.layout_tests.port import test
 from webkitpy.layout_tests.servers.apache_http import ApacheHTTP
 from webkitpy.layout_tests.servers.server_base import ServerError
 
 
 class TestApacheHTTP(unittest.TestCase):
@@ skipping 18 matching lines @@
         oc = OutputCapture()
         try:
             oc.capture_output()
             server.start()
             server.stop()
         finally:
             _, _, logs = oc.restore_output()
         self.assertIn("StartServers 4", logs)
         self.assertIn("MinSpareServers 4", logs)
         self.assertIn("MaxSpareServers 4", logs)