wlr_output: Add applied state to commit event

include/wlr/types/wlr_output.h

@@ -227,6 +227,7 @@ struct wlr_output_event_commit {
 	uint32_t committed; // bitmask of enum wlr_output_state_field
 	struct timespec *when;
 	struct wlr_buffer *buffer; // NULL if no buffer is committed
+	const struct wlr_output_state *state;
 };
 
 enum wlr_output_present_flag {

types/output/output.c

@@ -836,6 +836,7 @@ bool wlr_output_commit_state(struct wlr_output *output,
 		.committed = pending.committed,
 		.when = &now,
 		.buffer = (pending.committed & WLR_OUTPUT_STATE_BUFFER) ? pending.buffer : NULL,
+		.state = &pending,
 	};
 	wl_signal_emit_mutable(&output->events.commit, &event);