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, 21 insertions, 10 deletions

diff --git a/components/script/script_thread.rs b/components/script/script_thread.rs
index cd2008bf56b..fe102a0a7b3 100644
--- a/components/script/script_thread.rs
+++ b/components/script/script_thread.rs
@@ -70,6 +70,7 @@ use crate::microtask::{Microtask, MicrotaskQueue};
 use crate::script_runtime::{get_reports, new_rt_and_cx, Runtime, ScriptPort};
 use crate::script_runtime::{CommonScriptMsg, ScriptChan, ScriptThreadEventCategory};
 use crate::serviceworkerjob::{Job, JobQueue};
+use crate::task_manager::TaskManager;
 use crate::task_queue::{QueuedTask, QueuedTaskConversion, TaskQueue};
 use crate::task_source::dom_manipulation::DOMManipulationTaskSource;
 use crate::task_source::file_reading::FileReadingTaskSource;
@@ -521,7 +522,7 @@ pub struct ScriptThread {
 
     networking_task_sender: Box<dyn ScriptChan>,
 
-    history_traversal_task_source: HistoryTraversalTaskSource,
+    history_traversal_task_sender: Sender<MainThreadScriptMsg>,
 
     file_reading_task_sender: Box<dyn ScriptChan>,
 
@@ -1042,7 +1043,7 @@ impl ScriptThread {
             performance_timeline_task_sender: boxed_script_sender.clone(),
             remote_event_task_sender: boxed_script_sender.clone(),
 
-            history_traversal_task_source: HistoryTraversalTaskSource(chan),
+            history_traversal_task_sender: chan.clone(),
 
             control_chan: state.control_chan,
             control_port: control_port,
@@ -1409,6 +1410,7 @@ impl ScriptThread {
                 ScriptThreadEventCategory::FormPlannedNavigation => {
                     ProfilerCategory::ScriptPlannedNavigation
                 },
+                ScriptThreadEventCategory::HistoryEvent => ProfilerCategory::ScriptHistoryEvent,
                 ScriptThreadEventCategory::ImageCacheMsg => ProfilerCategory::ScriptImageCacheMsg,
                 ScriptThreadEventCategory::InputEvent => ProfilerCategory::ScriptInputEvent,
                 ScriptThreadEventCategory::NetworkEvent => ProfilerCategory::ScriptNetworkEvent,
@@ -2180,6 +2182,13 @@ impl ScriptThread {
         PerformanceTimelineTaskSource(self.performance_timeline_task_sender.clone(), pipeline_id)
     }
 
+    pub fn history_traversal_task_source(
+        &self,
+        pipeline_id: PipelineId,
+    ) -> HistoryTraversalTaskSource {
+        HistoryTraversalTaskSource(self.history_traversal_task_sender.clone(), pipeline_id)
+    }
+
     pub fn user_interaction_task_source(
         &self,
         pipeline_id: PipelineId,
@@ -2560,7 +2569,6 @@ impl ScriptThread {
         );
 
         let MainThreadScriptChan(ref sender) = self.chan;
-        let HistoryTraversalTaskSource(ref history_sender) = self.history_traversal_task_source;
 
         let (ipc_timer_event_chan, ipc_timer_event_port) = ipc::channel().unwrap();
         route_ipc_receiver_to_new_servo_sender(ipc_timer_event_port, self.timer_event_chan.clone());
@@ -2576,20 +2584,23 @@ impl ScriptThread {
             pipeline_id: incomplete.pipeline_id,
         };
 
-        // Create the window and document objects.
-        let window = Window::new(
-            self.js_runtime.clone(),
-            MainThreadScriptChan(sender.clone()),
+        let task_manager = TaskManager::new(
             self.dom_manipulation_task_source(incomplete.pipeline_id),
+            self.file_reading_task_source(incomplete.pipeline_id),
+            self.history_traversal_task_source(incomplete.pipeline_id),
             self.media_element_task_source(incomplete.pipeline_id),
-            self.user_interaction_task_source(incomplete.pipeline_id),
             self.networking_task_source(incomplete.pipeline_id),
-            HistoryTraversalTaskSource(history_sender.clone()),
-            self.file_reading_task_source(incomplete.pipeline_id),
             self.performance_timeline_task_source(incomplete.pipeline_id)
                 .clone(),
+            self.user_interaction_task_source(incomplete.pipeline_id),
             self.remote_event_task_source(incomplete.pipeline_id),
             self.websocket_task_source(incomplete.pipeline_id),
+        );
+        // Create the window and document objects.
+        let window = Window::new(
+            self.js_runtime.clone(),
+            MainThreadScriptChan(sender.clone()),
+            task_manager,
             self.image_cache_channel.clone(),
             self.image_cache.clone(),
             self.resource_threads.clone(),