Simplify transactions by utilising a dirty flag on containers

This PR changes the way we handle transactions to a more simple method.
The new method is to mark containers as dirty from low level code
(eg. arranging, or container_destroy, and eventually seat_set_focus),
then call transaction_commit_dirty which picks up those containers and
runs them through a transaction. The old methods of using transactions
(arrange_and_commit, or creating one manually) are now no longer
possible.

The highest-level code (execute_command and view implementation
handlers) will call transaction_commit_dirty, so most other code just
needs to set containers as dirty. This is done by arranging, but can
also be done by calling container_set_dirty.

1 files changed, 2 insertions, 1 deletions

diff --git a/sway/tree/layout.c b/sway/tree/layout.c
index ba234e89..54ddb3f9 100644
--- a/sway/tree/layout.c
+++ b/sway/tree/layout.c
@@ -22,7 +22,8 @@ struct sway_container root_container;
 
 static void output_layout_handle_change(struct wl_listener *listener,
                 void *data) {
-        arrange_and_commit(&root_container);
+        arrange_windows(&root_container);
+        transaction_commit_dirty();
 }
 
 void layout_init(void) {