Remove workarounds for versions of Python before 2.7
https://bugs.webkit.org/show_bug.cgi?id=137338

Reviewed by Csaba Osztrogonác.

* Scripts/webkitpy/common/system/autoinstall.py:
(AutoInstaller._extract_targz):
(AutoInstaller._unzip):
(AutoInstaller): Deleted.
(AutoInstaller._extract_all): Deleted.
* Scripts/webkitpy/common/webkitunittest.py:
(TestCase.setUp): Deleted.
* Scripts/webkitpy/layout_tests/models/test_configuration.py:
(TestConfigurationConverter.collapse_macros):
(TestConfigurationConverter.to_specifiers_list.try_collapsing):
(TestConfigurationConverter.to_specifiers_list.try_abbreviating):
(TestConfigurationConverter):
(TestConfigurationConverter.combinations): Deleted.
* Scripts/webkitpy/layout_tests/models/test_expectations_unittest.py:
* Scripts/webkitpy/port/base.py:


git-svn-id: http://svn.webkit.org/repository/webkit/trunk@174266 268f45cc-cd09-0410-ab3c-d52691b4dbfc