contrib/git-svn: create a more recent master if one does not exist

In a new repository, the initial fetch creates a master branch
if one does not exist so HEAD has something to point to.

It now creates a master at the end of the initial fetch run,
pointing to the latest revision.  Previously it pointed to the
first revision imported, which is generally less useful.

Signed-off-by: Eric Wong <normalperson@yhbt.net>
Signed-off-by: Junio C Hamano <junkio@cox.net>
diff --git a/contrib/git-svn/git-svn.perl b/contrib/git-svn/git-svn.perl
index 5d547e8..69b6be3 100755
--- a/contrib/git-svn/git-svn.perl
+++ b/contrib/git-svn/git-svn.perl
@@ -224,9 +224,6 @@
 		sys(@svn_co, $SVN_URL, $SVN_WC);
 		chdir $SVN_WC or croak $!;
 		$last_commit = git_commit($base, @parents);
-		unless (-f "$GIT_DIR/refs/heads/master") {
-			sys(qw(git-update-ref refs/heads/master),$last_commit);
-		}
 		assert_svn_wc_clean($base->{revision}, $last_commit);
 	} else {
 		chdir $SVN_WC or croak $!;
@@ -242,6 +239,9 @@
 		$last_commit = git_commit($log_msg, $last_commit, @parents);
 	}
 	assert_svn_wc_clean($last_rev, $last_commit);
+	unless (-e "$GIT_DIR/refs/heads/master") {
+		sys(qw(git-update-ref refs/heads/master),$last_commit);
+	}
 	return pop @$svn_log;
 }