LibWeb: Add comments and missing items of various IDL files

Userland/Libraries/LibWeb/DOM/AbortController.idl

@@ -1,5 +1,6 @@
 #import <DOM/AbortSignal.idl>
 
+// https://dom.spec.whatwg.org/#interface-abortcontroller
 [Exposed=(Window,Worker)]
 interface AbortController {
     constructor();

Userland/Libraries/LibWeb/DOM/AbortSignal.idl

@@ -1,9 +1,12 @@
 #import <DOM/EventTarget.idl>
 #import <DOM/EventHandler.idl>
 
+// https://dom.spec.whatwg.org/#interface-AbortSignal
 [Exposed=(Window,Worker), CustomVisit]
 interface AbortSignal : EventTarget {
     // FIXME: [NewObject] static AbortSignal abort(optional any reason);
+    // FIXME: [Exposed=(Window,Worker), NewObject] static AbortSignal timeout([EnforceRange] unsigned long long milliseconds);
+    // FIXME: [NewObject] static AbortSignal _any(sequence<AbortSignal> signals);
 
     readonly attribute boolean aborted;
     readonly attribute any reason;

Userland/Libraries/LibWeb/DOM/AbstractRange.idl

@@ -1,3 +1,4 @@
+// https://dom.spec.whatwg.org/#interface-abstractrange
 [Exposed=Window]
 interface AbstractRange {
     readonly attribute Node startContainer;

Userland/Libraries/LibWeb/DOM/Attr.idl

@@ -1,6 +1,7 @@
 #import <DOM/Node.idl>
 #import <DOM/Element.idl>
 
+// https://dom.spec.whatwg.org/#interface-attr
 [Exposed=Window]
 interface Attr : Node {
     readonly attribute DOMString? namespaceURI;
@@ -11,5 +12,5 @@ interface Attr : Node {
 
     readonly attribute Element? ownerElement;
 
-    readonly attribute boolean specified;
+    readonly attribute boolean specified; // useless; always returns true
 };

Userland/Libraries/LibWeb/DOM/CDATASection.idl

@@ -1,3 +1,4 @@
+// https://dom.spec.whatwg.org/#interface-cdatasection
 [Exposed=Window]
 interface CDATASection : Text {
 };

Userland/Libraries/LibWeb/DOM/CharacterData.idl

@@ -14,8 +14,9 @@ interface CharacterData : Node {
     undefined deleteData(unsigned long offset, unsigned long count);
     undefined replaceData(unsigned long offset, unsigned long count, DOMString data);
 
-    readonly attribute Element? nextElementSibling;
+    // https://dom.spec.whatwg.org/#interface-nondocumenttypechildnode
     readonly attribute Element? previousElementSibling;
+    readonly attribute Element? nextElementSibling;
 };
 
 CharacterData includes ChildNode;

Userland/Libraries/LibWeb/DOM/CustomEvent.idl

@@ -1,5 +1,6 @@
 #import <DOM/Event.idl>
 
+// https://dom.spec.whatwg.org/#interface-customevent
 [Exposed=(Window,Worker)]
 interface CustomEvent : Event {
     constructor(DOMString type, optional CustomEventInit eventInitDict = {});

Userland/Libraries/LibWeb/DOM/DocumentFragment.idl

@@ -9,6 +9,7 @@
 interface DocumentFragment : Node {
     constructor();
 
+    // https://dom.spec.whatwg.org/#interface-nonelementparentnode
     Element? getElementById(DOMString id);
 };
 

Userland/Libraries/LibWeb/DOM/Event.idl

@@ -8,7 +8,7 @@ interface Event {
 
     readonly attribute DOMString type;
     readonly attribute EventTarget? target;
-    readonly attribute EventTarget? srcElement;
+    readonly attribute EventTarget? srcElement; // legacy
     readonly attribute EventTarget? currentTarget;
     sequence<EventTarget> composedPath();
 

Userland/Libraries/LibWeb/DOM/HTMLCollection.idl

@@ -1,5 +1,6 @@
 #import <DOM/Element.idl>
 
+// https://dom.spec.whatwg.org/#interface-htmlcollection
 [Exposed=Window, LegacyUnenumerableNamedProperties]
 interface HTMLCollection {
 

Userland/Libraries/LibWeb/DOM/MutationObserver.idl

@@ -1,6 +1,7 @@
 #import <DOM/MutationRecord.idl>
 #import <DOM/Node.idl>
 
+// https://dom.spec.whatwg.org/#interface-mutationobserver
 [Exposed=Window]
 interface MutationObserver {
 

Userland/Libraries/LibWeb/DOM/MutationRecord.idl

@@ -1,6 +1,7 @@
 #import <DOM/Node.idl>
 #import <DOM/NodeList.idl>
 
+// https://dom.spec.whatwg.org/#interface-mutationrecord
 [Exposed=Window]
 interface MutationRecord {
 

Userland/Libraries/LibWeb/DOM/NamedNodeMap.idl

@@ -1,5 +1,6 @@
 #import <DOM/Attr.idl>
 
+// https://dom.spec.whatwg.org/#interface-namednodemap
 [Exposed=Window, LegacyUnenumerableNamedProperties]
 interface NamedNodeMap {
     readonly attribute unsigned long length;

Userland/Libraries/LibWeb/DOM/NodeIterator.idl

@@ -1,6 +1,7 @@
 #import <DOM/Node.idl>
 #import <DOM/NodeFilter.idl>
 
+// https://dom.spec.whatwg.org/#interface-nodeiterator
 [Exposed=Window]
 interface NodeIterator {
 

Userland/Libraries/LibWeb/DOM/NodeList.idl

@@ -1,5 +1,6 @@
 #import <DOM/Node.idl>
 
+// https://dom.spec.whatwg.org/#interface-nodelist
 [Exposed=Window]
 interface NodeList {
     getter Node? item(unsigned long index);

Userland/Libraries/LibWeb/DOM/Range.idl

@@ -2,6 +2,7 @@
 #import <DOM/AbstractRange.idl>
 #import <Geometry/DOMRect.idl>
 
+// https://dom.spec.whatwg.org/#interface-range
 [Exposed=Window]
 interface Range : AbstractRange {
 

Userland/Libraries/LibWeb/DOM/StaticRange.idl

@@ -1,6 +1,7 @@
 #import <DOM/Node.idl>
 #import <DOM/AbstractRange.idl>
 
+// https://dom.spec.whatwg.org/#staticrange
 [Exposed=Window]
 interface StaticRange : AbstractRange {
     constructor(StaticRangeInit init);

Userland/Libraries/LibWeb/DOM/TreeWalker.idl

@@ -1,6 +1,7 @@
 #import <DOM/Node.idl>
 #import <DOM/NodeFilter.idl>
 
+// https://dom.spec.whatwg.org/#interface-treewalker
 [Exposed=Window]
 interface TreeWalker {
 

Userland/Libraries/LibWeb/DOM/XMLDocument.idl

@@ -1,5 +1,6 @@
 #import <DOM/Document.idl>
 
+// https://dom.spec.whatwg.org/#xmldocument
 [Exposed=Window]
 interface XMLDocument : Document {
 };