vim-patch:8.2.0907: when using :global clipboard isn't set correctly

Problem:    When using :global clipboard isn't set correctly.
Solution:   Set "clip_unnamed_saved" instead of "clip_unnamed". (Christian
            Brabandt, closes vim/vim#6203, closes vim/vim#6198)
07188fc5ef

src/nvim/testdir/test_global.vim

@@ -1,3 +1,4 @@
+source check.vim
 
 func Test_yank_put_clipboard()
   new
@@ -10,6 +11,16 @@ func Test_yank_put_clipboard()
   bwipe!
 endfunc
 
+func Test_global_set_clipboard()
+  CheckFeature clipboard_working
+  new
+  set clipboard=unnamedplus
+  let @+='clipboard' | g/^/set cb= | let @" = 'unnamed' | put
+  call assert_equal(['','unnamed'], getline(1, '$'))
+  set clipboard&
+  bwipe!
+endfunc
+
 func Test_nested_global()
   new
   call setline(1, ['nothing', 'found', 'found bad', 'bad'])