fix: Solve several accessible-name issues

lib/checks/shared/aria-label.js

@@ -1,2 +1 @@
-var label = node.getAttribute('aria-label');
-return !!(label ? axe.commons.text.sanitize(label).trim() : '');
+return !!axe.commons.aria.getAriaLabelText(node);

lib/checks/shared/aria-labelledby.js

@@ -1,5 +1 @@
-var getIdRefs = axe.commons.dom.idrefs;
-
-return getIdRefs(node, 'aria-labelledby').some(function(elm) {
-	return elm && axe.commons.text.accessibleText(elm, true);
-});
+return !!axe.commons.aria.getAriaLabelledbyText(node);

lib/commons/aria/get-aria-label-text.js

@@ -0,0 +1,9 @@
+/* global aria, text */
+aria.getAriaLabelText = function getAriaLabelText(node) {
+	node = node.actualNode || node;
+	if (node.nodeType !== 1) {
+		return '';
+	}
+	var label = node && node.getAttribute('aria-label');
+	return label ? text.sanitize(label) : '';
+};

lib/commons/aria/get-aria-labelledby-text.js

@@ -0,0 +1,37 @@
+/* global aria, dom, text */
+aria.getAriaLabelledbyText = function getAriaLabelledbyText(node, context) {
+	node = node.actualNode || node;
+	/**
+	 * Note: The there are significant difference in how many "leads" browsers follow.
+	 * - Firefox stops after the first IDREF, so it
+	 * 		doesn't follow aria-labelledby after a for:>ID ref.
+	 * - Chrome seems to just keep iterating no matter how many levels deep.
+	 * - AccName-AAM 1.1 suggests going one level deep, but to treat
+	 * 		each ref type separately.
+	 *
+	 * Axe-core's implementation behaves most closely like Firefox as it seems
+	 *  to be the most common deniminator. Main difference is that Firefox
+	 *  includes the value of form controls in addition to aria-label(s),
+	 *  something no other browser seems to do. Axe doesn't do that.
+	 */
+	if (
+		node.nodeType !== 1 ||
+		context.inLabelledByContext ||
+		context.inControlContext
+	) {
+		return '';
+	}
+
+	const refs = dom.idrefs(node, 'aria-labelledby').filter(elm => elm);
+	return refs.reduce((accessibleName, elm) => {
+		const accessibleNameAdd = text.accessibleText(elm, {
+			// Prevent the infinite reference loop:
+			inLabelledByContext: true,
+			// Allow hidden content if
+			includeHidden: !dom.isVisible(elm, true),
+			...context
+		});
+
+		return (accessibleName + ' ' + accessibleNameAdd).trim();
+	}, '');
+};

lib/commons/aria/get-owned.js

@@ -0,0 +1,10 @@
+/* global aria, dom */
+aria.getOwnedVirtual = function getOwned({ actualNode, children }) {
+	return dom.idrefs(actualNode, 'aria-owns').reduce((ownedElm, element) => {
+		if (element) {
+			let virtualNode = axe.utils.getNodeFromTree(axe._tree[0], element);
+			ownedElm.push(virtualNode);
+		}
+		return ownedElm;
+	}, children);
+};

lib/commons/aria/get-role.js

@@ -18,6 +18,10 @@ aria.getRole = function getRole(
 	node,
 	{ noImplicit, fallback, abstracts, dpub } = {}
 ) {
+	node = node.actualNode || node;
+	if (node.nodeType !== 1) {
+		return null;
+	}
 	const roleAttr = (node.getAttribute('role') || '').trim().toLowerCase();
 	const roleList = fallback ? axe.utils.tokenList(roleAttr) : [roleAttr];