webkitpy: Make webkit_base() protected.

third_party/WebKit/Tools/Scripts/webkitpy/common/webkit_finder_unittest.py

 # Copyright 2016 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 import unittest
 
 from webkitpy.common.webkit_finder import WebKitFinder
 from webkitpy.common.system.filesystem_mock import MockFileSystem
 
 
 class TestWebKitFinder(unittest.TestCase):
 
     # TODO(qyearsley): Add tests for other methods in WebKitFinder.
     # Including tests for cases when the separator character is backslash.
 
     def test_layout_test_name(self):
         finder = WebKitFinder(MockFileSystem())
         self.assertEqual(
             finder.layout_test_name('third_party/WebKit/LayoutTests/test/name.html'),
             'test/name.html')
 
     def test_layout_test_name_not_in_layout_tests_dir(self):
         finder = WebKitFinder(MockFileSystem())
         self.assertIsNone(finder.layout_test_name('some/other/path/file.html'))
 
+    # pylint: disable=protected-access
     def test_webkit_base(self):
         finder = WebKitFinder(MockFileSystem())
-        self.assertEqual(finder.webkit_base(), '/mock-checkout/third_party/WebKit')
+        self.assertEqual(finder._webkit_base(), '/mock-checkout/third_party/WebKit')
 
     def test_chromium_base(self):
         finder = WebKitFinder(MockFileSystem())
         self.assertEqual(finder.chromium_base(), '/mock-checkout')
 
     def test_path_from_chromium_base(self):
         finder = WebKitFinder(MockFileSystem())
         self.assertEqual(
             finder.path_from_chromium_base('foo', 'bar.baz'),
             '/mock-checkout/foo/bar.baz')