Rather than having two grids for each pane, one for ASCII and one for

UTF-8, collapse the two together. Simplifies the code at the expense of
more memory (which can probably be reduced again later).

format.c

@@ -370,7 +370,6 @@ format_window_pane(struct format_tree *ft, struct window_pane *wp)
 	for (i = 0; i < gd->hsize; i++) {
 		gl = &gd->linedata[i];
 		size += gl->cellsize * sizeof *gl->celldata;
-		size += gl->utf8size * sizeof *gl->utf8data;
 	}
 	size += gd->hsize * sizeof *gd->linedata;