cairo-util: Set geometry_dirty in frame_set_title

Title can decide the geometry of a frame because it may affect the
existence of titlebar, so setting geometry_dirty in frame_set_title for
potential change.

Signed-off-by: Boyan Ding <stu_dby@126.com>

shared/frame.c

@@ -385,6 +385,7 @@ frame_set_title(struct frame *frame, const char *title)
 	free(frame->title);
 	frame->title = dup;
 
+	frame->geometry_dirty = 1;
 	frame->status |= FRAME_STATUS_REPAINT;
 
 	return 0;