script: Move HTML DOM interfaces to script/dom/html/ (#39046)

See #38901.

Testing: Refactor
Fixes: Partially #38901

Signed-off-by: Ashwin Naren <arihant2math@gmail.com>

components/script/dom/html/htmllegendelement.rs

@@ -0,0 +1,112 @@
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this
+// file, You can obtain one at https://mozilla.org/MPL/2.0/.
+
+use dom_struct::dom_struct;
+use html5ever::{LocalName, Prefix};
+use js::rust::HandleObject;
+
+use crate::dom::bindings::codegen::Bindings::HTMLLegendElementBinding::HTMLLegendElementMethods;
+use crate::dom::bindings::codegen::Bindings::NodeBinding::NodeMethods;
+use crate::dom::bindings::inheritance::Castable;
+use crate::dom::bindings::root::{DomRoot, MutNullableDom};
+use crate::dom::document::Document;
+use crate::dom::element::Element;
+use crate::dom::html::htmlelement::HTMLElement;
+use crate::dom::html::htmlfieldsetelement::HTMLFieldSetElement;
+use crate::dom::html::htmlformelement::{FormControl, HTMLFormElement};
+use crate::dom::node::{BindContext, Node, UnbindContext};
+use crate::dom::virtualmethods::VirtualMethods;
+use crate::script_runtime::CanGc;
+
+#[dom_struct]
+pub(crate) struct HTMLLegendElement {
+    htmlelement: HTMLElement,
+    form_owner: MutNullableDom<HTMLFormElement>,
+}
+
+impl HTMLLegendElement {
+    fn new_inherited(
+        local_name: LocalName,
+        prefix: Option<Prefix>,
+        document: &Document,
+    ) -> HTMLLegendElement {
+        HTMLLegendElement {
+            htmlelement: HTMLElement::new_inherited(local_name, prefix, document),
+            form_owner: Default::default(),
+        }
+    }
+
+    #[cfg_attr(crown, allow(crown::unrooted_must_root))]
+    pub(crate) fn new(
+        local_name: LocalName,
+        prefix: Option<Prefix>,
+        document: &Document,
+        proto: Option<HandleObject>,
+        can_gc: CanGc,
+    ) -> DomRoot<HTMLLegendElement> {
+        Node::reflect_node_with_proto(
+            Box::new(HTMLLegendElement::new_inherited(
+                local_name, prefix, document,
+            )),
+            document,
+            proto,
+            can_gc,
+        )
+    }
+}
+
+impl VirtualMethods for HTMLLegendElement {
+    fn super_type(&self) -> Option<&dyn VirtualMethods> {
+        Some(self.upcast::<HTMLElement>() as &dyn VirtualMethods)
+    }
+
+    fn bind_to_tree(&self, context: &BindContext, can_gc: CanGc) {
+        if let Some(s) = self.super_type() {
+            s.bind_to_tree(context, can_gc);
+        }
+
+        self.upcast::<Element>()
+            .check_ancestors_disabled_state_for_form_control();
+    }
+
+    fn unbind_from_tree(&self, context: &UnbindContext, can_gc: CanGc) {
+        self.super_type().unwrap().unbind_from_tree(context, can_gc);
+
+        let node = self.upcast::<Node>();
+        let el = self.upcast::<Element>();
+        if node
+            .ancestors()
+            .any(|ancestor| ancestor.is::<HTMLFieldSetElement>())
+        {
+            el.check_ancestors_disabled_state_for_form_control();
+        } else {
+            el.check_disabled_attribute();
+        }
+    }
+}
+
+impl HTMLLegendElementMethods<crate::DomTypeHolder> for HTMLLegendElement {
+    // https://html.spec.whatwg.org/multipage/#dom-legend-form
+    fn GetForm(&self) -> Option<DomRoot<HTMLFormElement>> {
+        let parent = self.upcast::<Node>().GetParentElement()?;
+        if parent.is::<HTMLFieldSetElement>() {
+            return self.form_owner();
+        }
+        None
+    }
+}
+
+impl FormControl for HTMLLegendElement {
+    fn form_owner(&self) -> Option<DomRoot<HTMLFormElement>> {
+        self.form_owner.get()
+    }
+
+    fn set_form_owner(&self, form: Option<&HTMLFormElement>) {
+        self.form_owner.set(form);
+    }
+
+    fn to_element(&self) -> &Element {
+        self.upcast::<Element>()
+    }
+}