Rollup merge of #16885 - jonathanGB:master, r=jdm

Bug 1270740 - remove requestAutocomplete reference

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I was in charge of removing the `requestAutocomplete` feature in [mozilla-central](https://bugzilla.mozilla.org/show_bug.cgi?id=1270740), and needed to remove a reference to that feature in the **servo** comments. The change, therefore, is really trivial.

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

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- [X] These changes do not require tests because I simply removed a comment

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components/script/dom/webidls/HTMLFormElement.webidl

@@ -24,6 +24,4 @@ interface HTMLFormElement : HTMLElement {
   void reset();
   //boolean checkValidity();
   //boolean reportValidity();
-
-  //void requestAutocomplete();
 };