git-svn: split the path from the url correctly with limited perms

git-svn: split the path from the url correctly with limited perms

This version of the splitter (that only affects SVN:: library
users) works when one only has limited read-permissions to
the repository they're fetching from.

Updated from the original patch to workaround some SVN bug
somewhere, which only seems to happen against file://
repositories...  Here's the diff against the original patch I
submitted:

@@ -1159,8 +1159,8 @@ sub repo_path_split {
 	}

 	if ($_use_lib) {
-		$SVN = libsvn_connect($full_url);
-		my $url = $SVN->get_repos_root;
+		my $tmp = libsvn_connect($full_url);
+		my $url = $tmp->get_repos_root;
 		$full_url =~ s#^\Q$url\E/*##;
 		push @repo_path_split_cache, qr/^(\Q$url\E)/;
 		return ($url, $full_url);

Somehow connecting to a repository with the full url makes the
returned SVN::Ra object act strangely and break things, so now
we just drop the SVN::Ra object that we made our initial
connection with.

Signed-off-by: Eric Wong <normalperson@yhbt.net>
Signed-off-by: Junio C Hamano <junkio@cox.net>