Auto merge of #24312 - SiddharthaMishra:master, r=jdm

don't send progress event for empty blob

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- [X] `./mach test-tidy` does not report any errors
- [X] These changes fix #24289 (GitHub issue number if applicable)

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1 files changed, 4 insertions, 2 deletions

diff --git a/components/script/dom/filereader.rs b/components/script/dom/filereader.rs
index 2cf7baff144..95b0572c3c5 100644
--- a/components/script/dom/filereader.rs
+++ b/components/script/dom/filereader.rs
@@ -494,8 +494,10 @@ fn perform_annotated_read_operation(
     let task = FileReadingTask::ProcessRead(filereader.clone(), gen_id);
     task_source.queue_with_canceller(task, &canceller).unwrap();
 
-    let task = FileReadingTask::ProcessReadData(filereader.clone(), gen_id);
-    task_source.queue_with_canceller(task, &canceller).unwrap();
+    if !blob_contents.is_empty() {
+        let task = FileReadingTask::ProcessReadData(filereader.clone(), gen_id);
+        task_source.queue_with_canceller(task, &canceller).unwrap();
+    }
 
     let task = FileReadingTask::ProcessReadEOF(filereader, gen_id, data, blob_contents);
     task_source.queue_with_canceller(task, &canceller).unwrap();