Auto merge of #14274 - stshine:servo-url-index, r=emilio

Implement range index with the Position enum on ServoUrl

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- [ ] These changes fix #__ (github issue number if applicable).

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r? @emilio

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components/script/script_thread.rs

@@ -1739,7 +1739,7 @@ impl ScriptThread {
             // Start with the scheme data of the parsed URL;
             // append question mark and query component, if any;
             // append number sign and fragment component if any.
-            let encoded = &incomplete.url.as_url().unwrap()[Position::BeforePath..];
+            let encoded = &incomplete.url[Position::BeforePath..];
 
             // Percent-decode (8.) and UTF-8 decode (9.)
             let script_source = percent_decode(encoded.as_bytes()).decode_utf8_lossy();