Auto merge of #12404 - ConnorGBrewster:task_source_cleanup, r=asajeffrey

Clean up task sources and make all tasks cancellable

<!-- Please describe your changes on the following line: -->
This makes it so each task is a thin wrapper over a runnable and whenever a task is queued, it is automatically wrapped by the window's `runnable_wrapper`.

---
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- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] These changes fix  #11703 (github issue number if applicable).

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- [ ] There are tests for these changes OR
- [ ] These changes do not require tests because _____

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1 files changed, 3 insertions, 2 deletions

diff --git a/components/script/dom/htmlscriptelement.rs b/components/script/dom/htmlscriptelement.rs
index 2d10e5f43d8..5195b0e53a6 100644
--- a/components/script/dom/htmlscriptelement.rs
+++ b/components/script/dom/htmlscriptelement.rs
@@ -460,12 +460,13 @@ impl HTMLScriptElement {
         if external {
             self.dispatch_load_event();
         } else {
-            window.dom_manipulation_task_source().queue_simple_event(self.upcast(), atom!("load"));
+            window.dom_manipulation_task_source().queue_simple_event(self.upcast(), atom!("load"), window.r());
         }
     }
 
     pub fn queue_error_event(&self) {
-        window_from_node(self).dom_manipulation_task_source().queue_simple_event(self.upcast(), atom!("error"));
+        let window = window_from_node(self);
+        window.dom_manipulation_task_source().queue_simple_event(self.upcast(), atom!("error"), window.r());
     }
 
     pub fn dispatch_before_script_execute_event(&self) -> bool {