output-damage: stop using enum wlr_output_state_buffer_type

This enum will get dropped in the next commit.

include/wlr/types/wlr_output_damage.h

@@ -43,7 +43,7 @@ struct wlr_output_damage {
 	pixman_region32_t previous[WLR_OUTPUT_DAMAGE_PREVIOUS_LEN];
 	size_t previous_idx;
 
-	enum wlr_output_state_buffer_type pending_buffer_type;
+	bool pending_attach_render;
 
 	struct {
 		struct wl_signal frame;

types/wlr_output_damage.c

@@ -52,11 +52,8 @@ static void output_handle_precommit(struct wl_listener *listener, void *data) {
 	if (output->pending.committed & WLR_OUTPUT_STATE_BUFFER) {
 		// TODO: find a better way to access this info without a precommit
 		// handler
-		if (output->back_buffer != NULL) {
-			output_damage->pending_buffer_type = WLR_OUTPUT_STATE_BUFFER_RENDER;
-		} else {
-			output_damage->pending_buffer_type = output->pending.buffer_type;
-		}
+		output_damage->pending_attach_render = output->back_buffer != NULL ||
+			output->pending.buffer_type == WLR_OUTPUT_STATE_BUFFER_RENDER;
 	}
 }
 
@@ -74,8 +71,7 @@ static void output_handle_commit(struct wl_listener *listener, void *data) {
 	}
 
 	pixman_region32_t *prev;
-	switch (output_damage->pending_buffer_type) {
-	case WLR_OUTPUT_STATE_BUFFER_RENDER:
+	if (output_damage->pending_attach_render) {
 		// render-buffers have been swapped, rotate the damage
 
 		// same as decrementing, but works on unsigned integers
@@ -84,12 +80,10 @@ static void output_handle_commit(struct wl_listener *listener, void *data) {
 
 		prev = &output_damage->previous[output_damage->previous_idx];
 		pixman_region32_copy(prev, &output_damage->current);
-		break;
-	case WLR_OUTPUT_STATE_BUFFER_SCANOUT:
+	} else {
 		// accumulate render-buffer damage
 		prev = &output_damage->previous[output_damage->previous_idx];
 		pixman_region32_union(prev, prev, &output_damage->current);
-		break;
 	}
 
 	pixman_region32_clear(&output_damage->current);