Subject: bug#16897: 24.3.50; vc-print-root-log doesn't show the top commit if it's a merge commit

From: Stefan Monnier <[email-masked]>
Date: Sat, 01 Mar 2014 12:13:27 -0500

> This sort of assumes that default-directory is always the root dir.

Obviously, we'd want to compare to root-dir, not to default-dir.
And we'd want to cache the result so as to avoid looking for the root
directory repeatedly.

        Stefan