Auto merge of #150 - KiChjang:origin-doc, r=SimonSapin

Use triple slash for documentation on Url::origin method

I was a dumb-dumb and didn't add an additional slash for rustdocs.

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src/lib.rs

@@ -635,7 +635,7 @@ impl Url {
         self.to_string()
     }
 
-    // Return the origin of this URL (https://url.spec.whatwg.org/#origin)
+    /// Return the origin of this URL (https://url.spec.whatwg.org/#origin)
     pub fn origin(&self) -> Origin {
         match &*self.scheme {
             "blob" => {