patch 8.2.1727: a popup created with "cursorline" will ignore "firstline"

Problem:    A popup created with "cursorline" will ignore "firstline".
Solution:   When both "cursorline" and "firstline" are present put the cursor
            on "firstline". (closes #7000)  Add the "winid" argument to
            getcurpos().
diff --git a/src/testdir/test_functions.vim b/src/testdir/test_functions.vim
index 7ff9b7a..2492c93 100644
--- a/src/testdir/test_functions.vim
+++ b/src/testdir/test_functions.vim
@@ -2520,7 +2520,19 @@
   call assert_equal('6', @")
   call assert_equal(-1, setpos('.', test_null_list()))
   call assert_equal(-1, setpos('.', {}))
+
+  let winid = win_getid()
+  normal G$
+  let pos = getcurpos()
+  wincmd w
+  call assert_equal(pos, getcurpos(winid))
+
+  wincmd w
   close!
+
+  call assert_equal(getcurpos(), getcurpos(0))
+  call assert_equal([0, 0, 0, 0, 0], getcurpos(-1))
+  call assert_equal([0, 0, 0, 0, 0], getcurpos(1999))
 endfunc
 
 " Test for glob()