C++ PATCH to dfs_find_final_overrider

[Jason Merrill]

The old logic failed to handle the case where there was a previous
best overrider ambiguous with a new one; basically, it would never catch
ambiguities.  Fixed; test below.

This is a regression from 2.95.

Tested i686-pc-linux-gnu, applied to trunk.  Again, I think this will go
onto the branch after the 3.0 release has gone out.

2001-06-14  Jason Merrill  <jason_merrill@redhat.com>

	* class.c (dfs_find_final_overrider): Fix logic.