patch 9.0.0114: the command line takes up space even when not used

Problem:    The command line takes up space even when not used.
Solution:   Allow for 'cmdheight' to be set to zero. (Shougo Matsushita,
            closes #10675, closes #940)
diff --git a/src/testdir/gen_opt_test.vim b/src/testdir/gen_opt_test.vim
index 83f43f7..a552160 100644
--- a/src/testdir/gen_opt_test.vim
+++ b/src/testdir/gen_opt_test.vim
@@ -27,7 +27,7 @@
 " Two lists with values: values that work and values that fail.
 " When not listed, "othernum" or "otherstring" is used.
 let test_values = {
-      \ 'cmdheight': [[1, 2, 10], [-1, 0]],
+      \ 'cmdheight': [[0, 1, 2, 10], [-1]],
       \ 'cmdwinheight': [[1, 2, 10], [-1, 0]],
       \ 'columns': [[12, 80], [-1, 0, 10]],
       \ 'conceallevel': [[0, 1, 2, 3], [-1, 4, 99]],