Remove offset argument to container_add_sibling

I added this thinking that it might come in useful. Turns out it didn't.

include/sway/tree/container.h

@@ -279,7 +279,7 @@ void container_insert_child(struct sway_container *parent,
 		struct sway_container *child, int i);
 
 void container_add_sibling(struct sway_container *parent,
-		struct sway_container *child, int offset);
+		struct sway_container *child);
 
 void container_detach(struct sway_container *child);
 

sway/commands/move.c

@@ -233,7 +233,7 @@ static void container_move_to_container(struct sway_container *container,
 	container->saved_width = container->saved_height = 0;
 
 	if (destination->view) {
-		container_add_sibling(destination, container, 1);
+		container_add_sibling(destination, container);
 	} else {
 		container_add_child(destination, container);
 	}

sway/tree/container.c

@@ -1079,13 +1079,13 @@ void container_insert_child(struct sway_container *parent,
 }
 
 void container_add_sibling(struct sway_container *fixed,
-		struct sway_container *active, int offset) {
+		struct sway_container *active) {
 	if (active->workspace) {
 		container_detach(active);
 	}
 	list_t *siblings = container_get_siblings(fixed);
 	int index = list_find(siblings, fixed);
-	list_insert(siblings, index + offset, active);
+	list_insert(siblings, index + 1, active);
 	active->parent = fixed->parent;
 	active->workspace = fixed->workspace;
 	container_for_each_child(active, set_workspace, NULL);
@@ -1136,7 +1136,7 @@ void container_detach(struct sway_container *child) {
 
 void container_replace(struct sway_container *container,
 		struct sway_container *replacement) {
-	container_add_sibling(container, replacement, 1);
+	container_add_sibling(container, replacement);
 	container_detach(container);
 }
 

sway/tree/view.c

@@ -515,7 +515,7 @@ void view_map(struct sway_view *view, struct wlr_surface *wlr_surface) {
 
 	view->container = container_create(view);
 	if (target_sibling) {
-		container_add_sibling(target_sibling, view->container, 1);
+		container_add_sibling(target_sibling, view->container);
 	} else {
 		workspace_add_tiling(ws, view->container);
 	}