patch 8.1.1787: cannot resize a popup window

Problem:    Cannot resize a popup window.
Solution:   Allow for resizing by dragging the lower right corncer.
diff --git a/src/ui.c b/src/ui.c
index 4e05859..c8cedb9 100644
--- a/src/ui.c
+++ b/src/ui.c
@@ -3067,10 +3067,11 @@
 		popup_close_for_mouse_click(wp);
 		return IN_UNKNOWN;
 	    }
-	    else if (wp->w_popup_drag && popup_on_border(wp, row, col))
+	    else if ((wp->w_popup_flags & (POPF_DRAG | POPF_RESIZE))
+					      && popup_on_border(wp, row, col))
 	    {
 		popup_dragwin = wp;
-		popup_start_drag(wp);
+		popup_start_drag(wp, row, col);
 		return IN_UNKNOWN;
 	    }
 	    // Only close on release, otherwise it's not possible to drag or do