Add webkitpy platform support for Mac 10.10 Yosemite.

Tools/Scripts/webkitpy/layout_tests/port/port_testcase.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 271 matching lines @@
             TestConfiguration('snowleopard', 'x86', 'debug'),
             TestConfiguration('snowleopard', 'x86', 'release'),
             TestConfiguration('lion', 'x86', 'debug'),
             TestConfiguration('lion', 'x86', 'release'),
             TestConfiguration('retina', 'x86', 'debug'),
             TestConfiguration('retina', 'x86', 'release'),
             TestConfiguration('mountainlion', 'x86', 'debug'),
             TestConfiguration('mountainlion', 'x86', 'release'),
             TestConfiguration('mavericks', 'x86', 'debug'),
             TestConfiguration('mavericks', 'x86', 'release'),
+            TestConfiguration('yosemite', 'x86', 'debug'),
+            TestConfiguration('yosemite', 'x86', 'release'),
             TestConfiguration('xp', 'x86', 'debug'),
             TestConfiguration('xp', 'x86', 'release'),
             TestConfiguration('win7', 'x86', 'debug'),
             TestConfiguration('win7', 'x86', 'release'),
             TestConfiguration('lucid', 'x86', 'debug'),
             TestConfiguration('lucid', 'x86', 'release'),
             TestConfiguration('lucid', 'x86_64', 'debug'),
             TestConfiguration('lucid', 'x86_64', 'release'),
             TestConfiguration('icecreamsandwich', 'x86', 'debug'),
             TestConfiguration('icecreamsandwich', 'x86', 'release'),
@@ skipping 177 matching lines @@
     def test_additional_platform_directory(self):
         port = self.make_port(options=MockOptions(additional_platform_directory=['/tmp/foo']))
         self.assertEqual(port.baseline_search_path()[0], '/tmp/foo')
 
     def test_virtual_test_suites(self):
         # We test that we can load the real LayoutTests/VirtualTestSuites file properly, so we
         # use a real SystemHost(). We don't care what virtual_test_suites() returns as long
         # as it is iterable.
         port = self.make_port(host=SystemHost(), port_name=self.full_port_name)
         self.assertTrue(isinstance(port.virtual_test_suites(), collections.Iterable))