LibWeb/HTML: Update cloning steps to current spec algorithms

Reflects the changes in whatwg/html#10859

I've also added missing calls to the Base::cloned() method, and modified
a couple of spec links to point to the multipage version.

I took the liberty to fix a spec typo, and submitted a PR for it:
whatwg/html#10892

Author: AtkinsSJ

Libraries/LibWeb/HTML/HTMLInputElement.cpp

@@ -1660,9 +1660,11 @@ void HTMLInputElement::apply_presentational_hints(GC::Ref<CSS::CascadedPropertie
 }
 
 // https://html.spec.whatwg.org/multipage/input.html#the-input-element%3Aconcept-node-clone-ext
-WebIDL::ExceptionOr<void> HTMLInputElement::cloned(DOM::Node& copy, bool)
+WebIDL::ExceptionOr<void> HTMLInputElement::cloned(DOM::Node& copy, bool subtree)
 {
-    // The cloning steps for input elements must propagate the value, dirty value flag, checkedness, and dirty checkedness flag from the node being cloned to the copy.
+    TRY(Base::cloned(copy, subtree));
+
+    // The cloning steps for input elements given node, copy, and subtree are to propagate the value, dirty value flag, checkedness, and dirty checkedness flag from node to copy.
     auto& input_clone = verify_cast<HTMLInputElement>(copy);
     input_clone.m_value = m_value;
     input_clone.m_dirty_value = m_dirty_value;

Libraries/LibWeb/HTML/HTMLOrSVGElement.cpp

@@ -56,7 +56,7 @@ void HTMLOrSVGElement<ElementBase>::blur()
     // User agents may selectively or uniformly ignore calls to this method for usability reasons.
 }
 
-// https://html.spec.whatwg.org/#dom-noncedelement-nonce
+// https://html.spec.whatwg.org/multipage/urls-and-fetching.html#dom-noncedelement-nonce
 template<typename ElementBase>
 void HTMLOrSVGElement<ElementBase>::attribute_changed(FlyString const& local_name, Optional<String> const&, Optional<String> const& value, Optional<FlyString> const& namespace_)
 {
@@ -76,17 +76,17 @@ void HTMLOrSVGElement<ElementBase>::attribute_changed(FlyString const& local_nam
     }
 }
 
-// https://html.spec.whatwg.org/#dom-noncedelement-nonce
+// https://html.spec.whatwg.org/multipage/urls-and-fetching.html#dom-noncedelement-nonce
 template<typename ElementBase>
 WebIDL::ExceptionOr<void> HTMLOrSVGElement<ElementBase>::cloned(DOM::Node& copy, bool)
 {
-    // The cloning steps for elements that include HTMLOrSVGElement must set the
-    // [[CryptographicNonce]] slot on the copy to the value of the slot on the element being cloned.
+    // The cloning steps for elements that include HTMLOrSVGElement given node, copy, and subtree
+    // are to set copy's [[CryptographicNonce]] to node's [[CryptographicNonce]].
     static_cast<ElementBase&>(copy).m_cryptographic_nonce = m_cryptographic_nonce;
     return {};
 }
 
-// https://html.spec.whatwg.org/#dom-noncedelement-nonce
+// https://html.spec.whatwg.org/multipage/urls-and-fetching.html#dom-noncedelement-nonce
 template<typename ElementBase>
 void HTMLOrSVGElement<ElementBase>::inserted()
 {

Libraries/LibWeb/HTML/HTMLTemplateElement.cpp

@@ -46,20 +46,24 @@ void HTMLTemplateElement::adopted_from(DOM::Document&)
 }
 
 // https://html.spec.whatwg.org/multipage/scripting.html#the-template-element:concept-node-clone-ext
-WebIDL::ExceptionOr<void> HTMLTemplateElement::cloned(Node& copy, bool clone_children)
+WebIDL::ExceptionOr<void> HTMLTemplateElement::cloned(Node& copy, bool subtree)
 {
-    // 1. If the clone children flag is not set in the calling clone algorithm, return.
-    if (!clone_children)
+    TRY(Base::cloned(copy, subtree));
+
+    // The cloning steps for template elements given node, copy, and subtree are:
+
+    // 1. If subtree is false, then return.
+    if (!subtree)
         return {};
 
-    // 2. Let copied contents be the result of cloning all the children of node's template contents,
-    //    with document set to copy's template contents's node document, and with the clone children flag set.
-    // 3. Append copied contents to copy's template contents.
-    auto& template_clone = verify_cast<HTMLTemplateElement>(copy);
+    // 2. For each child of node's template contents's children, in tree order:
+    //    clone a node given child with document set to copy's template contents's node document,
+    //    subtree set to true, and parent set to copy's template contents.
+    auto& template_copy = verify_cast<HTMLTemplateElement>(copy);
     for (auto child = content()->first_child(); child; child = child->next_sibling()) {
-        auto cloned_child = TRY(child->clone_node(&template_clone.content()->document(), true));
-        TRY(template_clone.content()->append_child(cloned_child));
+        TRY(child->clone_node(&template_copy.content()->document(), true, template_copy.content()));
     }
+
     return {};
 }
 

Libraries/LibWeb/HTML/HTMLTextAreaElement.cpp

@@ -136,9 +136,11 @@ void HTMLTextAreaElement::clear_algorithm()
 }
 
 // https://html.spec.whatwg.org/multipage/forms.html#the-textarea-element:concept-node-clone-ext
-WebIDL::ExceptionOr<void> HTMLTextAreaElement::cloned(DOM::Node& copy, bool)
+WebIDL::ExceptionOr<void> HTMLTextAreaElement::cloned(DOM::Node& copy, bool subtree)
 {
-    // The cloning steps for textarea elements must propagate the raw value and dirty value flag from the node being cloned to the copy.
+    TRY(Base::cloned(copy, subtree));
+
+    // The cloning steps for textarea elements given node, copy, and subtree are to propagate the raw value and dirty value flag from node to copy.
     auto& textarea_copy = verify_cast<HTMLTextAreaElement>(copy);
     textarea_copy.m_raw_value = m_raw_value;
     textarea_copy.m_dirty_value = m_dirty_value;