Auto merge of #21804 - AgustinCB:unify-task-source-canceller-api, r=gterzian

Unify the task source and task canceller API

To do so, I created a struct `TaskManagement(TaskSource,
TaskCanceller)` and made `*_task_source` return that instead of just
the task source.

Next, I refactored all places in which `task_canceller` by basically
removing them in favour of a previously called `*_task_source`.

I tried to make `task_canceller` a private method in `Window`, with the
hope of enforcing the use of `*_task_source`. However, it's used in
components/script/dom/globalscope.rs:575 in such a way that will make it
harder to avoid. I decided to leave it that way.

It'd be possible to unify `*_task_source` in such a way that we would
have only one method. However, I decided not to do it because one of the
`TaskSource` implementations is special:
`history_traversal_task_source`. Not wanting to over complicate things,
I decided to leave the structure this way.

---
- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] These changes fix #21154 (github issue number if applicable).

- [x] These changes do not require tests because it's refactoring code that should already be tested.

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1 files changed, 5 insertions, 4 deletions

diff --git a/components/script/dom/audioscheduledsourcenode.rs b/components/script/dom/audioscheduledsourcenode.rs
index 31527fda3de..24437b88db9 100644
--- a/components/script/dom/audioscheduledsourcenode.rs
+++ b/components/script/dom/audioscheduledsourcenode.rs
@@ -10,7 +10,7 @@ use crate::dom::bindings::inheritance::Castable;
 use crate::dom::bindings::num::Finite;
 use crate::dom::bindings::refcounted::Trusted;
 use crate::dom::bindings::reflector::DomObject;
-use crate::task_source::{TaskSource, TaskSourceName};
+use crate::task_source::TaskSource;
 use dom_struct::dom_struct;
 use servo_media::audio::node::OnEndedCallback;
 use servo_media::audio::node::{AudioNodeInit, AudioNodeMessage, AudioScheduledSourceNodeMessage};
@@ -71,15 +71,16 @@ impl AudioScheduledSourceNodeMethods for AudioScheduledSourceNode {
         let this = Trusted::new(self);
         let global = self.global();
         let window = global.as_window();
-        let task_source = window.dom_manipulation_task_source();
-        let canceller = window.task_canceller(TaskSourceName::DOMManipulation);
+        let (task_source, canceller) = window
+            .task_manager()
+            .dom_manipulation_task_source_with_canceller();
         let callback = OnEndedCallback::new(move || {
             let _ = task_source.queue_with_canceller(
                 task!(ended: move || {
                     let this = this.root();
                     let global = this.global();
                     let window = global.as_window();
-                    window.dom_manipulation_task_source().queue_simple_event(
+                    window.task_manager().dom_manipulation_task_source().queue_simple_event(
                         this.upcast(),
                         atom!("ended"),
                         &window