patch 8.0.0485: not all windows commands are tested

Problem:    Not all windows commands are tested.
Solution:   Add more tests for windows commands. (Dominique Pelle,
            closes #1575) Run test_autocmd separately, it interferes with
            other tests.  Fix tests that depended on side effects.
diff --git a/src/testdir/test_fnamemodify.vim b/src/testdir/test_fnamemodify.vim
index 1c2a80d..768d311 100644
--- a/src/testdir/test_fnamemodify.vim
+++ b/src/testdir/test_fnamemodify.vim
@@ -33,8 +33,8 @@
   call assert_equal('''abc"%"def''', fnamemodify('abc"%"def', ':S'))
   call assert_equal('''abc''\'''' ''\''''def''', fnamemodify('abc'' ''def', ':S'))
   call assert_equal('''abc''\''''%''\''''def''', fnamemodify('abc''%''def', ':S'))
-  call assert_equal(expand('%:r:S'), shellescape(expand('%:r')))
   sp test_alot.vim
+  call assert_equal(expand('%:r:S'), shellescape(expand('%:r')))
   call assert_equal('test_alot,''test_alot'',test_alot.vim', join([expand('%:r'), expand('%:r:S'), expand('%')], ','))
   quit