git-svn: fix processing of decorated commit hashes

The function working_head_info() fails to parse commit hashes if they
are decorated (i.e. log.decorate is true), causing dcommit, rebase, and
other vital git-svn commands to malfunction.

This patch disables decorated log output with --no-decorate.

[ew: wrapped long line]

Signed-off-by: Mathias Lafeldt <misfire@debugon.org>
Acked-by: Eric Wong <normalperson@yhbt.net>

git-svn.perl

@@ -1513,7 +1513,8 @@ sub cmt_sha2rev_batch {
 
 sub working_head_info {
 	my ($head, $refs) = @_;
-	my @args = ('log', '--no-color', '--first-parent', '--pretty=medium');
+	my @args = qw/log --no-color --no-decorate --first-parent
+	              --pretty=medium/;
 	my ($fh, $ctx) = command_output_pipe(@args, $head);
 	my $hash;
 	my %max;