patch 9.0.1048: with "screenline" in 'culopt' cursorline highlight is wrong

Problem:    With "screenline" in 'culopt' cursorline highlight is wrong.
Solution:   Apply the priority logic also when "screenline is in 'culopt'.
            (closes #11696)
diff --git a/src/testdir/test_signs.vim b/src/testdir/test_signs.vim
index abf70cd..76cefa2 100644
--- a/src/testdir/test_signs.vim
+++ b/src/testdir/test_signs.vim
@@ -1805,12 +1805,18 @@
   call term_sendkeys(buf, "2G")
   call term_sendkeys(buf, ":\<CR>")
   call VerifyScreenDump(buf, 'Test_sign_cursor_5', {})
+  call term_sendkeys(buf, ":set cursorlineopt=number,screenline\<CR>")
+  call term_sendkeys(buf, ":\<CR>")
+  call VerifyScreenDump(buf, 'Test_sign_cursor_5', {})
 
   " sign highlighting overrules 'cursorline'
   call term_sendkeys(buf, ":sign unplace 12\<CR>")
   call term_sendkeys(buf, ":sign place 13 line=2 priority=100 name=s2\<CR>")
   call term_sendkeys(buf, ":\<CR>")
   call VerifyScreenDump(buf, 'Test_sign_cursor_6', {})
+  call term_sendkeys(buf, ":set cursorlineopt&\<CR>")
+  call term_sendkeys(buf, ":\<CR>")
+  call VerifyScreenDump(buf, 'Test_sign_cursor_6', {})
 
   " clean up
   call StopVimInTerminal(buf)