Auto merge of #12448 - jdm:file-reading-task-source-2, r=KiChjang

Implement file reading task source

Implement the task source API for the File Reader task source, enabling using task sources from non-main threads.

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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 (partially) #7959 (github issue number if applicable).
- [X] These changes do not require tests because they're refactoring existing code

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1 files changed, 1 insertions, 1 deletions

diff --git a/components/script/dom/window.rs b/components/script/dom/window.rs
index 9401eae5a46..30ab695f9b7 100644
--- a/components/script/dom/window.rs
+++ b/components/script/dom/window.rs
@@ -302,7 +302,7 @@ impl Window {
         self.history_traversal_task_source.clone()
     }
 
-    pub fn file_reading_task_source(&self) -> Box<ScriptChan + Send> {
+    pub fn file_reading_task_source(&self) -> FileReadingTaskSource {
         self.file_reading_task_source.clone()
     }