Change GitCL to initialize git executable name on Windows.

third_party/WebKit/Tools/Scripts/webkitpy/w3c/test_importer_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 collections
 
 from webkitpy.common.checkout.git_mock import MockGit
 from webkitpy.common.host_mock import MockHost
 from webkitpy.common.system.executive_mock import MockExecutive
 from webkitpy.common.system.log_testing import LoggingTestCase
@@ skipping 144 matching lines @@
                     blink_path + '/LayoutTests/external/WPT_BASE_MANIFEST.json',
                 ]
             ])
 
     def test_get_directory_owners(self):
         host = MockHost()
         host.filesystem.write_text_file(
             '/mock-checkout/third_party/WebKit/LayoutTests/W3CImportExpectations',
             '## Owners: someone@chromium.org\n'
             '# external/wpt/foo [ Pass ]\n')
-        git = MockGit()
+        git = MockGit(filesystem=host.filesystem, executive=host.executive, platform=host.platform)
         git.changed_files = lambda: ['third_party/WebKit/LayoutTests/external/wpt/foo/x.html']
         host.git = lambda: git
         importer = TestImporter(host)
         self.assertEqual(importer.get_directory_owners(), {('someone@chromium.org',): ['external/wpt/foo']})
 
     def test_get_directory_owners_no_changed_files(self):
         host = MockHost()
         host.filesystem.write_text_file(
             '/mock-checkout/third_party/WebKit/LayoutTests/W3CImportExpectations',
             '## Owners: someone@chromium.org\n'
@@ skipping 28 matching lines @@
         host.filesystem.write_text_file(dest_path + '/foo-test.html', '')
         host.filesystem.write_text_file(dest_path + '/foo-test-expected.txt', '')
         host.filesystem.write_text_file(dest_path + '/OWNERS', '')
         host.filesystem.write_text_file(dest_path + '/bar/baz/OWNERS', '')
         importer = TestImporter(host)
         importer._clear_out_dest_path(dest_path)
         self.assertFalse(host.filesystem.exists(dest_path + '/foo-test.html'))
         self.assertTrue(host.filesystem.exists(dest_path + '/foo-test-expected.txt'))
         self.assertTrue(host.filesystem.exists(dest_path + '/OWNERS'))
         self.assertTrue(host.filesystem.exists(dest_path + '/bar/baz/OWNERS'))