Implement iterators per container type

This introduces the following `for_each` functions:

* root_for_each_workspace
* root_for_each_container
* output_for_each_workspace
* output_for_each_container
* workspace_for_each_container

And introduces the following `find` functions:

* root_find_output
* root_find_workspace
* root_find_container
* output_find_workspace
* output_find_container
* workspace_find_container
* container_find_child

And removes the following functions:

* container_descendants
* container_for_each_descendant
* container_find

This change is preparing the way for demoting sway_container. Eventually
these functions will accept and return sway_outputs, sway_workspaces and
sway_containers (meaning a C_CONTAINER or C_VIEW).

This change also makes it easy to handle abnormalities like the
workspace floating list, root's scratchpad list and (once implemented)
root's saved workspaces list for when there's no connected outputs.

1 files changed, 1 insertions, 2 deletions

diff --git a/sway/commands/unmark.c b/sway/commands/unmark.c
index 44ceccee..c183785b 100644
--- a/sway/commands/unmark.c
+++ b/sway/commands/unmark.c
@@ -52,8 +52,7 @@ struct cmd_results *cmd_unmark(int argc, char **argv) {
 		view_find_and_unmark(mark);
 	} else {
 		// Remove all marks from all views
-		container_for_each_descendant(&root_container,
-				remove_all_marks_iterator, NULL);
+		root_for_each_container(remove_all_marks_iterator, NULL);
 	}
 	free(mark);