Auto merge of #12464 - aneeshusa:cleanup-start-sending-sniffed, r=Wafflespeanut

Remove fn start_sending_sniffed

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This function was not used, but more importantly encodes the bad
practice of a raw `.unwrap()` and therefore should not be used.

---
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- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [ ] These changes reference #12462 (github issue number if applicable).

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- [ ] There are tests for these changes OR
- [x] These changes do not require tests because they are a cleanup

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components/net/resource_thread.rs

@@ -94,14 +94,6 @@ pub fn send_error(url: Url, err: NetworkError, start_chan: LoadConsumer) {
     }
 }
 
-/// For use by loaders in responding to a Load message that allows content sniffing.
-pub fn start_sending_sniffed(start_chan: LoadConsumer, metadata: Metadata,
-                             classifier: Arc<MimeClassifier>, partial_body: &[u8],
-                             context: LoadContext)
-                             -> ProgressSender {
-    start_sending_sniffed_opt(start_chan, metadata, classifier, partial_body, context).ok().unwrap()
-}
-
 /// For use by loaders in responding to a Load message that allows content sniffing.
 pub fn start_sending_sniffed_opt(start_chan: LoadConsumer, mut metadata: Metadata,
                                  classifier: Arc<MimeClassifier>, partial_body: &[u8],