[23] add @noreference to DOM additions for preview features

org.eclipse.jdt.core/dom/org/eclipse/jdt/core/dom/ImportDeclaration.java

@@ -181,6 +181,7 @@ public static List propertyDescriptors(int apiLevel) {
 	 * @exception UnsupportedOperationException if this operation is used in
 	 * an AST below JLS23
 	 * @since 3.39
+	 * @noreference preview feature
 	 */
 	public List modifiers() {
 		if (this.ast.apiLevel < AST.JLS23_INTERNAL)
@@ -202,6 +203,7 @@ public List modifiers() {
 	 * @return the bit-wise "or" of <code>Modifier</code> constants
 	 * @see Modifier
 	 * @since 3.39
+	 * @noreference preview feature
 	 */
 	public int getModifiers() {
 		if (this.modifiers == null) {

org.eclipse.jdt.core/dom/org/eclipse/jdt/core/dom/Javadoc.java

@@ -334,6 +334,7 @@ public List tags() {
 	 * @return <code>true</code> if this is a markdown comment,
 	 *    and <code>false</code> if this is a traditional javadoc comment.
 	 * @since 3.39
+	 * @noreference preview feature
 	 */
 	public boolean isMarkdown() {
 		if (this.ast.apiLevel < AST.JLS23_INTERNAL) {
@@ -348,6 +349,7 @@ public boolean isMarkdown() {
 	 * @param isMarkdown <code>true</code> if this is a markdown comment,
 	 *    and <code>false</code> if this is a traditional javadoc comment.
 	 * @since 3.39
+	 * @noreference preview feature
 	 */
 	public void setMarkdown(boolean isMarkdown) {
 		if (this.ast.apiLevel < AST.JLS23_INTERNAL) {

org.eclipse.jdt.core/dom/org/eclipse/jdt/core/dom/Modifier.java

@@ -807,6 +807,7 @@ public boolean isNonSealed() {
 	 *
 	 * @return true if the receiver is the module modifier, false otherwise
 	 * @since 3.39
+	 * @noreference preview feature
 	 */
 	public static boolean isModule(int flags) {
 		return (flags & Modifier.MODULE) != 0;