webkitpy: Remove contents of directory.

third_party/WebKit/Tools/Scripts/webkitpy/common/system/filesystem_mock.py

Index: third_party/WebKit/Tools/Scripts/webkitpy/common/system/filesystem_mock.py
diff --git a/third_party/WebKit/Tools/Scripts/webkitpy/common/system/filesystem_mock.py b/third_party/WebKit/Tools/Scripts/webkitpy/common/system/filesystem_mock.py
index e4d94a1e47c81fcc21a729a80d3328faed508370..2655f9b76b39ab8dc1633c901aad39281d9f69c2 100644
--- a/third_party/WebKit/Tools/Scripts/webkitpy/common/system/filesystem_mock.py
+++ b/third_party/WebKit/Tools/Scripts/webkitpy/common/system/filesystem_mock.py
@@ -35,6 +35,8 @@ import unittest
 
 
 class MockFileSystem(object):
+    # pylint: disable=unused-argument
+
     sep = '/'
     pardir = '..'
 
@@ -386,13 +388,13 @@ class MockFileSystem(object):
 
         return dot_dot + rel_path
 
-    def remove(self, path):
+    def remove(self, path, retry=True):
         if self.files[path] is None:
             self._raise_not_found(path)
         self.files[path] = None
         self.written_files[path] = None
 
-    def rmtree(self, path_to_remove):
+    def rmtree(self, path_to_remove, ignore_errors=True, onerror=None):
         path_to_remove = self.normpath(path_to_remove)
 
         for file_path in self.files: