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, 10 insertions, 7 deletions

diff --git a/components/script/dom/htmltextareaelement.rs b/components/script/dom/htmltextareaelement.rs
index 89ffff3e030..cb4929f4cab 100755
--- a/components/script/dom/htmltextareaelement.rs
+++ b/components/script/dom/htmltextareaelement.rs
@@ -565,13 +565,16 @@ impl VirtualMethods for HTMLTextAreaElement {
         } else if event.type_() == atom!("keypress") && !event.DefaultPrevented() {
             if event.IsTrusted() {
                 let window = window_from_node(self);
-                let _ = window.user_interaction_task_source().queue_event(
-                    &self.upcast(),
-                    atom!("input"),
-                    EventBubbles::Bubbles,
-                    EventCancelable::NotCancelable,
-                    &window,
-                );
+                let _ = window
+                    .task_manager()
+                    .user_interaction_task_source()
+                    .queue_event(
+                        &self.upcast(),
+                        atom!("input"),
+                        EventBubbles::Bubbles,
+                        EventCancelable::NotCancelable,
+                        &window,
+                    );
             }
         }
     }