Auto merge of #24123 - gterzian:redo_blob, r=jdm

Restructure Blob, structured serialization

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FIX #24052 and also address the "cloning" half of FIX #23917

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- [ ] These changes fix #___ (GitHub issue number if applicable)

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components/script/dom/dedicatedworkerglobalscope.rs

@@ -549,7 +549,7 @@ impl DedicatedWorkerGlobalScope {
                 Some(pipeline_id),
                 TaskSourceName::DOMManipulation,
             ))
-            .unwrap();
+            .expect("Sending to parent failed");
         Ok(())
     }
 }