git svn: fix empty directory creation

Avoid attempts to stat() the contents of '', which could happen
when the root directory is empty.  Additionally, remove the
unnecessary '_' stat optimization since it was confusing and
possibly throwing off the non-existent case.

[ew: fixed indentation, rewrote commit message]

Acked-by: Eric Wong <normalperson@yhbt.net>
Signed-off-by: Michael J. Kiwala <mkiwala@genome.wustl.edu>

git-svn.perl

diff --git a/git-svn.perl b/git-svn.perl
index b3b6964..09c4ca5 100755
--- a/git-svn.perl
+++ b/git-svn.perl
@@ -2836,8 +2836,9 @@
 	foreach my $d (sort keys %empty_dirs) {
 		$d = uri_decode($d);
 		$d =~ s/$strip//;
+		next unless length($d);
 		next if -d $d;
-		if (-e _) {
+		if (-e $d) {
 			warn "$d exists but is not a directory\n";
 		} else {
 			print "creating empty directory: $d\n";