scene: fix wlr_scene_send_frame_done() API

This doesn't work if scene outputs are not used as the primary output of
scene surfaces will always be NULL.

Therefore, take a wlr_scene_output instead of separate wlr_scene and
wlr_output arguments and rename the function to
wlr_scene_output_send_frame_done().

The actual behavior of the function is unchanged.

include/wlr/types/wlr_scene.h

@@ -201,13 +201,6 @@ struct wlr_scene *wlr_scene_create(void);
  */
 void wlr_scene_render_output(struct wlr_scene *scene, struct wlr_output *output,
 	int lx, int ly, pixman_region32_t *damage);
-/**
- * Call wlr_surface_send_frame_done() on all surfaces in the scene rendered by
- * wlr_scene_render_output() for which wlr_scene_surface->primary_output
- * matches the given output.
- */
-void wlr_scene_send_frame_done(struct wlr_scene *scene,
-	struct wlr_output *output, struct timespec *now);
 
 /**
  * Add a node displaying nothing but its children.
@@ -295,7 +288,13 @@ void wlr_scene_output_set_position(struct wlr_scene_output *scene_output,
  * Render and commit an output.
  */
 bool wlr_scene_output_commit(struct wlr_scene_output *scene_output);
-
+/**
+ * Call wlr_surface_send_frame_done() on all surfaces in the scene rendered by
+ * wlr_scene_output_commit() for which wlr_scene_surface->primary_output
+ * matches the given scene_output.
+ */
+void wlr_scene_output_send_frame_done(struct wlr_scene_output *scene_output,
+	struct timespec *now);
 /**
  * Call `iterator` on each surface in the scene-graph visible on the output,
  * with the surface's position in layout coordinates. The function is called

tinywl/tinywl.c

@@ -524,7 +524,7 @@ static void output_frame(struct wl_listener *listener, void *data) {
 
 	struct timespec now;
 	clock_gettime(CLOCK_MONOTONIC, &now);
-	wlr_scene_send_frame_done(scene, output->wlr_output, &now);
+	wlr_scene_output_send_frame_done(scene_output, &now);
 }
 
 static void server_new_output(struct wl_listener *listener, void *data) {

types/scene/wlr_scene.c

@@ -876,31 +876,6 @@ void wlr_scene_render_output(struct wlr_scene *scene, struct wlr_output *output,
 	pixman_region32_fini(&full_region);
 }
 
-static void scene_send_frame_done_iterator(struct wlr_scene_node *node,
-		struct wlr_output *output, struct timespec *now) {
-	if (!node->state.enabled) {
-		return;
-	}
-
-	if (node->type == WLR_SCENE_NODE_SURFACE) {
-		struct wlr_scene_surface *scene_surface =
-			wlr_scene_surface_from_node(node);
-		if (scene_surface->primary_output == output) {
-			wlr_surface_send_frame_done(scene_surface->surface, now);
-		}
-	}
-
-	struct wlr_scene_node *child;
-	wl_list_for_each(child, &node->state.children, state.link) {
-		scene_send_frame_done_iterator(child, output, now);
-	}
-}
-
-void wlr_scene_send_frame_done(struct wlr_scene *scene,
-		struct wlr_output *output, struct timespec *now) {
-	scene_send_frame_done_iterator(&scene->node, output, now);
-}
-
 static void scene_output_handle_destroy(struct wlr_addon *addon) {
 	struct wlr_scene_output *scene_output =
 		wl_container_of(addon, scene_output, addon);
@@ -1121,6 +1096,32 @@ bool wlr_scene_output_commit(struct wlr_scene_output *scene_output) {
 	return wlr_output_commit(output);
 }
 
+static void scene_output_send_frame_done_iterator(struct wlr_scene_node *node,
+		struct wlr_output *output, struct timespec *now) {
+	if (!node->state.enabled) {
+		return;
+	}
+
+	if (node->type == WLR_SCENE_NODE_SURFACE) {
+		struct wlr_scene_surface *scene_surface =
+			wlr_scene_surface_from_node(node);
+		if (scene_surface->primary_output == output) {
+			wlr_surface_send_frame_done(scene_surface->surface, now);
+		}
+	}
+
+	struct wlr_scene_node *child;
+	wl_list_for_each(child, &node->state.children, state.link) {
+		scene_output_send_frame_done_iterator(child, output, now);
+	}
+}
+
+void wlr_scene_output_send_frame_done(struct wlr_scene_output *scene_output,
+		struct timespec *now) {
+	scene_output_send_frame_done_iterator(&scene_output->scene->node,
+		scene_output->output, now);
+}
+
 static void scene_output_for_each_surface(const struct wlr_box *output_box,
 		struct wlr_scene_node *node, int lx, int ly,
 		wlr_surface_iterator_func_t user_iterator, void *user_data) {