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, 7 insertions, 4 deletions

diff --git a/components/script/stylesheet_loader.rs b/components/script/stylesheet_loader.rs
index 29144d48836..43d9cb3bb92 100644
--- a/components/script/stylesheet_loader.rs
+++ b/components/script/stylesheet_loader.rs
@@ -13,7 +13,6 @@ use crate::dom::htmlelement::HTMLElement;
 use crate::dom::htmllinkelement::{HTMLLinkElement, RequestGenerationId};
 use crate::dom::node::{document_from_node, window_from_node};
 use crate::network_listener::{NetworkListener, PreInvoke};
-use crate::task_source::TaskSourceName;
 use cssparser::SourceLocation;
 use encoding_rs::UTF_8;
 use ipc_channel::ipc;
@@ -245,10 +244,14 @@ impl<'a> StylesheetLoader<'a> {
         }));
 
         let (action_sender, action_receiver) = ipc::channel().unwrap();
+        let (task_source, canceller) = document
+            .window()
+            .task_manager()
+            .networking_task_source_with_canceller();
         let listener = NetworkListener {
-            context: context,
-            task_source: document.window().networking_task_source(),
-            canceller: Some(document.window().task_canceller(TaskSourceName::Networking)),
+            context,
+            task_source,
+            canceller: Some(canceller),
         };
         ROUTER.add_route(
             action_receiver.to_opaque(),