patch 9.1.0634: Ctrl-P not working by default

Problem:  Ctrl-P not working by default
          (Jesse Pavel, after v9.1.0598)
Solution: Revert part of v9.1.0598 and set cur_match_pos
          correctly according to compl_dir_forward()

fixes: #15370
closes: #15379

Signed-off-by: Christian Brabandt <cb@256bit.org>
diff --git a/src/testdir/test_ins_complete.vim b/src/testdir/test_ins_complete.vim
index f3f6eac..cf688ac 100644
--- a/src/testdir/test_ins_complete.vim
+++ b/src/testdir/test_ins_complete.vim
@@ -2688,4 +2688,14 @@
   set completeopt&
 endfunc
 
+func Test_complete_backwards_default()
+  new
+  call append(1, ['foobar', 'foobaz'])
+  new
+  call feedkeys("i\<c-p>", 'tx')
+  call assert_equal('foobaz', getline('.'))
+  bw!
+  bw!
+endfunc
+
 " vim: shiftwidth=2 sts=2 expandtab nofoldenable