Refactor destroy functions and save workspaces when there's no outputs

This changes the destroy functions to the following:

* output_begin_destroy
* output_destroy
* workspace_begin_destroy
* workspace_destroy
* container_begin_destroy
* container_destroy
* view_begin_destroy
* view_destroy

The terminology was `destroy` and `free`, and it has been changed to
`begin_destroy` and `destroy` respectively.

When the last output is disconnected, its workspaces will now be stashed
in the root. Upon connection of a new output they will be restored.

There is a new function `workspace_consider_destroy` which decides
whether the given workspace should be destroyed or not (ie. empty and
not visible).

Calling container_begin_destroy will no longer automatically reap the
parents. In some places we want to reap the parents and in some we
don't, so this is left to the caller.

container_reap_empty_recursive and container_reap_empty have been
combined into one function and it will recurse up the tree.

1 files changed, 2 insertions, 0 deletions

diff --git a/sway/tree/root.c b/sway/tree/root.c
index c27ff2c3..5602f0a0 100644
--- a/sway/tree/root.c
+++ b/sway/tree/root.c
@@ -39,6 +39,7 @@ void root_create(void) {
         wl_list_init(&root_container.sway_root->drag_icons);
         wl_signal_init(&root_container.sway_root->events.new_container);
         root_container.sway_root->scratchpad = create_list();
+        root_container.sway_root->saved_workspaces = create_list();
 
         root_container.sway_root->output_layout_change.notify =
                 output_layout_handle_change;
@@ -50,6 +51,7 @@ void root_destroy(void) {
         // sway_root
         wl_list_remove(&root_container.sway_root->output_layout_change.link);
         list_free(root_container.sway_root->scratchpad);
+        list_free(root_container.sway_root->saved_workspaces);
         wlr_output_layout_destroy(root_container.sway_root->output_layout);
         free(root_container.sway_root);