patch 9.0.1992: [security] segfault in exmode

Problem:  segfault in exmode when redrawing
Solution: skip gui_scroll when exmode_active

Signed-off-by: Christian Brabandt <cb@256bit.org>
diff --git a/src/testdir/test_crash.vim b/src/testdir/test_crash.vim
index 5c83e3a..9a80340 100644
--- a/src/testdir/test_crash.vim
+++ b/src/testdir/test_crash.vim
@@ -72,6 +72,12 @@
     \ '  || echo "crash 8: [OK]" >> X_crash1_result.txt' .. "\<cr>")
   call TermWait(buf, 3000)
 
+  let file = 'crash/crash_scrollbar'
+  let args = printf(cmn_args, vim, file)
+  call term_sendkeys(buf, args ..
+    \ '  && echo "crash 9: [OK]" >> X_crash1_result.txt' .. "\<cr>")
+  call TermWait(buf, 1000)
+
   " clean up
   exe buf .. "bw!"
 
@@ -86,6 +92,7 @@
       \ 'crash 6: [OK]',
       \ 'crash 7: [OK]',
       \ 'crash 8: [OK]',
+      \ 'crash 9: [OK]',
       \ ]
 
   call assert_equal(expected, getline(1, '$'))