Editorial: Align with Web IDL specification

[autokagami]

This is an automated pull request to align the spec with the latest Web IDL specification.

Currently the autofix might introduce some awkward code formatting, so please feel free to modify the formatting.

Please file an issue on https://github.com/saschanaz/webidl-updater/issues/new if you think this PR is invalid or should be enhanced.

The following is the validation messages from webidl2.js, which may help understanding this PR:

Validation error at line 17 in dom,0:
  void stopPropagation();
  ^ `void` is now replaced by `undefined`. Refer to the [relevant GitHub issue](https://github.com/heycam/webidl/issues/60) for more information.

Validation error at line 19 in dom,0:
  void stopImmediatePropagation();
  ^ `void` is now replaced by `undefined`. Refer to the [relevant GitHub issue](https://github.com/heycam/webidl/issues/60) for more information.

Validation error at line 24 in dom,0:
  void preventDefault();
  ^ `void` is now replaced by `undefined`. Refer to the [relevant GitHub issue](https://github.com/heycam/webidl/issues/60) for more information.

Validation error at line 31 in dom,0:
  void initEvent(DOMString type
  ^ `void` is now replaced by `undefined`. Refer to the [relevant GitHub issue](https://github.com/heycam/webidl/issues/60) for more information.

Validation error at line 7 in dom,2:
  void initCustomEvent(DOMString type
  ^ `void` is now replaced by `undefined`. Refer to the [relevant GitHub issue](https://github.com/heycam/webidl/issues/60) for more information.

Validation error at line 5 in dom,3:
  void addEventListener(DOMString type
  ^ `void` is now replaced by `undefined`. Refer to the [relevant GitHub issue](https://github.com/heycam/webidl/issues/60) for more information.

Validation error at line 6 in dom,3:
  void removeEventListener(DOMString type
  ^ `void` is now replaced by `undefined`. Refer to the [relevant GitHub issue](https://github.com/heycam/webidl/issues/60) for more information.

Validation error at line 11 in dom,3:
  void handleEvent(Event event
  ^ `void` is now replaced by `undefined`. Refer to the [relevant GitHub issue](https://github.com/heycam/webidl/issues/60) for more information.

Validation error at line 7 in dom,4:
  void abort();
  ^ `void` is now replaced by `undefined`. Refer to the [relevant GitHub issue](https://github.com/heycam/webidl/issues/60) for more information.

Validation error at line 7 in dom,8:
  [CEReactions, Unscopable] void prepend((Node
                            ^ `void` is now replaced by `undefined`. Refer to the [relevant GitHub issue](https://github.com/heycam/webidl/issues/60) for more information.

Validation error at line 8 in dom,8:
  [CEReactions, Unscopable] void append((Node
                            ^ `void` is now replaced by `undefined`. Refer to the [relevant GitHub issue](https://github.com/heycam/webidl/issues/60) for more information.

Validation error at line 9 in dom,8:
  [CEReactions, Unscopable] void replaceChildren((Node
                            ^ `void` is now replaced by `undefined`. Refer to the [relevant GitHub issue](https://github.com/heycam/webidl/issues/60) for more information.

Validation error at line 2 in dom,10:
  [CEReactions, Unscopable] void before((Node
                            ^ `void` is now replaced by `undefined`. Refer to the [relevant GitHub issue](https://github.com/heycam/webidl/issues/60) for more information.

Validation error at line 3 in dom,10:
  [CEReactions, Unscopable] void after((Node
                            ^ `void` is now replaced by `undefined`. Refer to the [relevant GitHub issue](https://github.com/heycam/webidl/issues/60) for more information.

Validation error at line 4 in dom,10:
  [CEReactions, Unscopable] void replaceWith((Node
                            ^ `void` is now replaced by `undefined`. Refer to the [relevant GitHub issue](https://github.com/heycam/webidl/issues/60) for more information.

Validation error at line 5 in dom,10:
  [CEReactions, Unscopable] void remove();
                            ^ `void` is now replaced by `undefined`. Refer to the [relevant GitHub issue](https://github.com/heycam/webidl/issues/60) for more information.

Validation error at line 5 in dom,14:
  void observe(Node target
  ^ `void` is now replaced by `undefined`. Refer to the [relevant GitHub issue](https://github.com/heycam/webidl/issues/60) for more information.

Validation error at line 6 in dom,14:
  void disconnect();
  ^ `void` is now replaced by `undefined`. Refer to the [relevant GitHub issue](https://github.com/heycam/webidl/issues/60) for more information.

Validation error at line 10 in dom,14:
callback MutationCallback = void (sequence<MutationRecord
                            ^ `void` is now replaced by `undefined`. Refer to the [relevant GitHub issue](https://github.com/heycam/webidl/issues/60) for more information.

Validation error at line 34 in dom,16:
  [CEReactions] void normalize();
                ^ `void` is now replaced by `undefined`. Refer to the [relevant GitHub issue](https://github.com/heycam/webidl/issues/60) for more information.

Validation error at line 18 in dom,22:
  [CEReactions] void setAttribute(DOMString qualifiedName
                ^ `void` is now replaced by `undefined`. Refer to the [relevant GitHub issue](https://github.com/heycam/webidl/issues/60) for more information.

Validation error at line 19 in dom,22:
  [CEReactions] void setAttributeNS(DOMString?
                ^ `void` is now replaced by `undefined`. Refer to the [relevant GitHub issue](https://github.com/heycam/webidl/issues/60) for more information.

Validation error at line 20 in dom,22:
  [CEReactions] void removeAttribute(DOMString qualifiedName
                ^ `void` is now replaced by `undefined`. Refer to the [relevant GitHub issue](https://github.com/heycam/webidl/issues/60) for more information.

Validation error at line 21 in dom,22:
  [CEReactions] void removeAttributeNS(DOMString?
                ^ `void` is now replaced by `undefined`. Refer to the [relevant GitHub issue](https://github.com/heycam/webidl/issues/60) for more information.

Validation error at line 44 in dom,22:
  void insertAdjacentText(DOMString where
  ^ `void` is now replaced by `undefined`. Refer to the [relevant GitHub issue](https://github.com/heycam/webidl/issues/60) for more information.

Validation error at line 6 in dom,25:
  void appendData(DOMString data
  ^ `void` is now replaced by `undefined`. Refer to the [relevant GitHub issue](https://github.com/heycam/webidl/issues/60) for more information.

Validation error at line 7 in dom,25:
  void insertData(unsigned long
  ^ `void` is now replaced by `undefined`. Refer to the [relevant GitHub issue](https://github.com/heycam/webidl/issues/60) for more information.

Validation error at line 8 in dom,25:
  void deleteData(unsigned long
  ^ `void` is now replaced by `undefined`. Refer to the [relevant GitHub issue](https://github.com/heycam/webidl/issues/60) for more information.

Validation error at line 9 in dom,25:
  void replaceData(unsigned long
  ^ `void` is now replaced by `undefined`. Refer to the [relevant GitHub issue](https://github.com/heycam/webidl/issues/60) for more information.

Validation error at line 7 in dom,32:
  void setStart(Node node
  ^ `void` is now replaced by `undefined`. Refer to the [relevant GitHub issue](https://github.com/heycam/webidl/issues/60) for more information.

Validation error at line 8 in dom,32:
  void setEnd(Node node
  ^ `void` is now replaced by `undefined`. Refer to the [relevant GitHub issue](https://github.com/heycam/webidl/issues/60) for more information.

Validation error at line 9 in dom,32:
  void setStartBefore(Node node
  ^ `void` is now replaced by `undefined`. Refer to the [relevant GitHub issue](https://github.com/heycam/webidl/issues/60) for more information.

Validation error at line 10 in dom,32:
  void setStartAfter(Node node
  ^ `void` is now replaced by `undefined`. Refer to the [relevant GitHub issue](https://github.com/heycam/webidl/issues/60) for more information.

Validation error at line 11 in dom,32:
  void setEndBefore(Node node
  ^ `void` is now replaced by `undefined`. Refer to the [relevant GitHub issue](https://github.com/heycam/webidl/issues/60) for more information.

Validation error at line 12 in dom,32:
  void setEndAfter(Node node
  ^ `void` is now replaced by `undefined`. Refer to the [relevant GitHub issue](https://github.com/heycam/webidl/issues/60) for more information.

Validation error at line 13 in dom,32:
  void collapse(optional boolean
  ^ `void` is now replaced by `undefined`. Refer to the [relevant GitHub issue](https://github.com/heycam/webidl/issues/60) for more information.

Validation error at line 14 in dom,32:
  void selectNode(Node node
  ^ `void` is now replaced by `undefined`. Refer to the [relevant GitHub issue](https://github.com/heycam/webidl/issues/60) for more information.

Validation error at line 15 in dom,32:
  void selectNodeContents(Node node
  ^ `void` is now replaced by `undefined`. Refer to the [relevant GitHub issue](https://github.com/heycam/webidl/issues/60) for more information.

Validation error at line 23 in dom,32:
  [CEReactions] void deleteContents();
                ^ `void` is now replaced by `undefined`. Refer to the [relevant GitHub issue](https://github.com/heycam/webidl/issues/60) for more information.

Validation error at line 26 in dom,32:
  [CEReactions] void insertNode(Node node
                ^ `void` is now replaced by `undefined`. Refer to the [relevant GitHub issue](https://github.com/heycam/webidl/issues/60) for more information.

Validation error at line 27 in dom,32:
  [CEReactions] void surroundContents(Node newParent
                ^ `void` is now replaced by `undefined`. Refer to the [relevant GitHub issue](https://github.com/heycam/webidl/issues/60) for more information.

Validation error at line 30 in dom,32:
  void detach();
  ^ `void` is now replaced by `undefined`. Refer to the [relevant GitHub issue](https://github.com/heycam/webidl/issues/60) for more information.

Validation error at line 12 in dom,33:
  void detach();
  ^ `void` is now replaced by `undefined`. Refer to the [relevant GitHub issue](https://github.com/heycam/webidl/issues/60) for more information.

Validation error at line 6 in dom,36:
  [CEReactions] void add(DOMString...
                ^ `void` is now replaced by `undefined`. Refer to the [relevant GitHub issue](https://github.com/heycam/webidl/issues/60) for more information.

Validation error at line 7 in dom,36:
  [CEReactions] void remove(DOMString...
                ^ `void` is now replaced by `undefined`. Refer to the [relevant GitHub issue](https://github.com/heycam/webidl/issues/60) for more information.

---

💥 Error: 500 Internal Server Error 💥

PR Preview failed to build. (Last tried on Aug 18, 2020, 4:34 PM UTC).

More

PR Preview relies on a number of web services to run. There seems to be an issue with the following one:

🚨 CSS Spec Preprocessor - CSS Spec Preprocessor is the web service used to build Bikeshed specs.

🔗 Related URL

<!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML 2.0//EN">
<html><head>
<title>500 Internal Server Error</title>
</head><body>
<h1>Internal Server Error</h1>
<p>The server encountered an internal error or
misconfiguration and was unable to complete
your request.</p>
<p>Please contact the server administrator at 
 [no address given] to inform them of the time this error occurred,
 and the actions you performed just before this error.</p>
<p>More information about this error may be available
in the server error log.</p>
<hr>
<address>Apache/2.4.10 (Debian) Server at api.csswg.org Port 443</address>
</body></html>

If you don't have enough information above to solve the error by yourself (or to understand to which web service the error is related to, if any), please file an issue.