vim-patch:8.2.2198: ml_get error when resizing window and using text property

Problem:    ml_get error when resizing window and using text property.
Solution:   Validate botline of the right window. (closes vim/vim#7528)

23999d799c

Migrate to Vim's (in)validate_botline_win() API.
Nvim wants to pass "curwin" instead of hiding them
behind alias/macro/inline-function.

https://github.com/neovim/neovim/pull/37164#discussion_r2655006908

Co-authored-by: Bram Moolenaar <Bram@vim.org>

src/nvim/diff.c

@@ -2535,7 +2535,7 @@ void diff_set_topline(win_T *fromwin, win_T *towin)
   }
 
   // When w_topline changes need to recompute w_botline and cursor position
-  invalidate_botline(towin);
+  invalidate_botline_win(towin);
   changed_line_abv_curs_win(towin);
 
   check_topfill(towin, false);