Fix submodule-merge-test.

tests/submodule-merge-test.sh

 #!/usr/bin/env bash
 
 # Copyright (c) 2012 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 set -e
 
 . ./test-lib.sh
 
@@ skipping 25 matching lines @@
       "test $next_svn_revision = `expr $prev_svn_revision + 1`"
 
   svn_diff=`svn diff -c $next_svn_revision file://$PWD/svnrepo | \
       sed -n '/^@@/,$p' | xargs`
 
   test_expect_success "svn diff is correct" \
       "test \"$git_diff\" = \"$svn_diff\""
 
   cd git-svn-submodule
   git svn fetch
-  last_svn_rev=`git show refs/remotes/trunk | grep git-svn-id: | \
+  last_svn_rev=`git show refs/remotes/origin/trunk | grep git-svn-id: | \
       grep -o trunk@[0-9]* | xargs`
 
   test_expect_success "git svn fetch gets new svn revision" \
       "test $last_svn_rev = trunk@$next_svn_revision"
 )
 SUCCESS=$?
 
 #cleanup
 
 if [ $SUCCESS == 0 ]; then
   echo PASS
 fi