LibWeb: Update innerHTML & co IDL definition to match spec

This stuff has moved from a mixin defined by the DOM Parsing spec, over
to the HTML spec, where they are now defined as partial interfaces for
Element and ShadowRoot.

There's also some new functionality that we don't implement yet, so
patch marks them as FIXME properties.

Userland/Libraries/LibWeb/DOM/Element.h

@@ -37,6 +37,11 @@ struct ShadowRootInit {
     bool serializable = false;
 };
 
+struct GetHTMLOptions {
+    bool serializable_shadow_roots { false };
+    Vector<JS::Handle<ShadowRoot>> shadow_roots {};
+};
+
 // https://w3c.github.io/csswg-drafts/cssom-view-1/#dictdef-scrollintoviewoptions
 struct ScrollIntoViewOptions : public HTML::ScrollOptions {
     Bindings::ScrollLogicalPosition block { Bindings::ScrollLogicalPosition::Start };

Userland/Libraries/LibWeb/DOM/Element.idl

@@ -3,7 +3,6 @@
 #import <DOM/Attr.idl>
 #import <DOM/ChildNode.idl>
 #import <DOM/DOMTokenList.idl>
-#import <DOM/InnerHTML.idl>
 #import <DOM/NamedNodeMap.idl>
 #import <DOM/Node.idl>
 #import <DOM/NodeList.idl>
@@ -94,12 +93,26 @@ interface Element : Node {
     readonly attribute long clientHeight;
     readonly attribute double currentCSSZoom;
 
-    // https://w3c.github.io/DOM-Parsing/#extensions-to-the-element-interface
+    // https://html.spec.whatwg.org/#dom-parsing-and-serialization
+    [FIXME, CEReactions] undefined setHTMLUnsafe((TrustedHTML or DOMString) html);
+    [FIXME] DOMString getHTML(optional GetHTMLOptions options = {});
+
+    // FIXME: [CEReactions] attribute (TrustedHTML or [LegacyNullToEmptyString] DOMString) innerHTML;
+    [CEReactions, LegacyNullToEmptyString] attribute DOMString innerHTML;
+
+    // FIXME: [CEReactions] attribute (TrustedHTML or [LegacyNullToEmptyString] DOMString) outerHTML;
     [CEReactions, LegacyNullToEmptyString] attribute DOMString outerHTML;
+
+    // FIXME: [CEReactions] undefined insertAdjacentHTML(DOMString position, (TrustedHTML or DOMString) string);
     [CEReactions] undefined insertAdjacentHTML(DOMString position, DOMString text);
 
 };
 
+dictionary GetHTMLOptions {
+    boolean serializableShadowRoots = false;
+    sequence<ShadowRoot> shadowRoots = [];
+};
+
 dictionary ShadowRootInit {
     required ShadowRootMode mode;
     boolean delegatesFocus = false;
@@ -110,7 +123,6 @@ dictionary ShadowRootInit {
 
 Element includes ParentNode;
 Element includes ChildNode;
-Element includes InnerHTML;
 // https://www.w3.org/TR/wai-aria-1.2/#idl_element
 Element includes ARIAMixin;
 Element includes Slottable;

Userland/Libraries/LibWeb/DOM/InnerHTML.idl

@@ -1,4 +0,0 @@
-// https://w3c.github.io/DOM-Parsing/#the-innerhtml-mixin
-interface mixin InnerHTML {
-    [LegacyNullToEmptyString, CEReactions] attribute DOMString innerHTML;
-};

Userland/Libraries/LibWeb/DOM/ShadowRoot.idl

@@ -1,6 +1,6 @@
 #import <DOM/DocumentFragment.idl>
 #import <DOM/DocumentOrShadowRoot.idl>
-#import <DOM/InnerHTML.idl>
+#import <DOM/Element.idl>
 
 // https://dom.spec.whatwg.org/#shadowroot
 [Exposed=Window]
@@ -12,9 +12,16 @@ interface ShadowRoot : DocumentFragment {
     readonly attribute boolean serializable;
     readonly attribute Element host;
     attribute EventHandler onslotchange;
+
+    // https://html.spec.whatwg.org/multipage/dynamic-markup-insertion.html#dom-parsing-and-serialization
+
+    [FIXME, CEReactions] undefined setHTMLUnsafe((TrustedHTML or DOMString) html);
+    [FIXME] DOMString getHTML(optional GetHTMLOptions options = {});
+
+    // FIXME: [CEReactions] attribute (TrustedHTML or [LegacyNullToEmptyString] DOMString) innerHTML;
+    [CEReactions, LegacyNullToEmptyString] attribute DOMString innerHTML;
 };
 
-ShadowRoot includes InnerHTML;
 ShadowRoot includes DocumentOrShadowRoot;
 
 enum ShadowRootMode { "open", "closed" };