Don't access Port._filesystem directly (use Port.host.filesystem instead).

third_party/WebKit/Tools/Scripts/webkitpy/layout_tests/port/linux_unittest.py

Index: third_party/WebKit/Tools/Scripts/webkitpy/layout_tests/port/linux_unittest.py
diff --git a/third_party/WebKit/Tools/Scripts/webkitpy/layout_tests/port/linux_unittest.py b/third_party/WebKit/Tools/Scripts/webkitpy/layout_tests/port/linux_unittest.py
index 6d718578fc9ff3653ce52d16bac815631b37e34a..f765b9320b2fa47b6912379bcfdb46f88436f4c6 100644
--- a/third_party/WebKit/Tools/Scripts/webkitpy/layout_tests/port/linux_unittest.py
+++ b/third_party/WebKit/Tools/Scripts/webkitpy/layout_tests/port/linux_unittest.py
@@ -105,16 +105,16 @@ class LinuxPortTest(port_testcase.PortTestCase):
     def test_dummy_home_dir_is_created_and_cleaned_up(self):
         port = self.make_port()
         port.host.environ['HOME'] = '/home/user'
-        port._filesystem.files['/home/user/.Xauthority'] = ''
+        port.host.filesystem.files['/home/user/.Xauthority'] = ''
 
         # Set up the test run; the temporary home directory should be set up.
         port.setup_test_run()
         temp_home_dir = port.host.environ['HOME']
         self.assertNotEqual(temp_home_dir, '/home/user')
-        self.assertTrue(port._filesystem.isdir(temp_home_dir))
-        self.assertTrue(port._filesystem.isfile(port._filesystem.join(temp_home_dir, '.Xauthority')))
+        self.assertTrue(port.host.filesystem.isdir(temp_home_dir))
+        self.assertTrue(port.host.filesystem.isfile(port.host.filesystem.join(temp_home_dir, '.Xauthority')))
 
         # Clean up; HOME should be reset and the temp dir should be cleaned up.
         port.clean_up_test_run()
         self.assertEqual(port.host.environ['HOME'], '/home/user')
-        self.assertFalse(port._filesystem.exists(temp_home_dir))
+        self.assertFalse(port.host.filesystem.exists(temp_home_dir))