patch 8.1.0864: cannot have a local value for 'scrolloff' and 'sidescrolloff'

Problem:    Cannot have a local value for 'scrolloff' and 'sidescrolloff'.
            (Gary Holloway)
Solution:   Make 'scrolloff' and 'sidescrolloff' global-local. (mostly by
            Aron Widforss, closes #3539)
diff --git a/src/testdir/test_options.vim b/src/testdir/test_options.vim
index 740863e..83b315d 100644
--- a/src/testdir/test_options.vim
+++ b/src/testdir/test_options.vim
@@ -483,3 +483,38 @@
   bwipe
   bwipe
 endfunc
+
+func Test_local_scrolloff()
+  set so=5
+  set siso=7
+  split
+  call assert_equal(5, &so)
+  setlocal so=3
+  call assert_equal(3, &so)
+  wincmd w
+  call assert_equal(5, &so)
+  wincmd w
+  setlocal so<
+  call assert_equal(5, &so)
+  setlocal so=0
+  call assert_equal(0, &so)
+  setlocal so=-1
+  call assert_equal(5, &so)
+
+  call assert_equal(7, &siso)
+  setlocal siso=3
+  call assert_equal(3, &siso)
+  wincmd w
+  call assert_equal(7, &siso)
+  wincmd w
+  setlocal siso<
+  call assert_equal(7, &siso)
+  setlocal siso=0
+  call assert_equal(0, &siso)
+  setlocal siso=-1
+  call assert_equal(7, &siso)
+
+  close
+  set so&
+  set siso&
+endfunc