+    Same a rmtree but uses safe functions to avoid race conditions
          ^
         typo

+                    onerror(os.unlinkat, os.path.join(path, name), sys.exc_info())
+        onerror(os.fwalk, path, sys.exc_info())

The documentation currently states that the first argument of onerror will be one of os.path.islink, os.listdir, os.remove, os.rmdir. You shuld probably add os.unlinkat and os.fwalk to that list now.

Otherwise, looks good to me.