Remove the css Selector and ShapeConverter constructors

Summary

Remove the deprecated public constructors javafx.css.Selector and javafx.css.converter.ShapeConverter

Problem

• Constructor for class javafx.css.Selector was deprecated for removal in openjfx16. It needs to be removed in openjfx17.
• Constructor for class javafx.css.converter.ShapeConverter was deprecated for removal in openjfx16. It needs to be removed in openjfx17.

Solution

• Constructor for class javafx.css.Selector is made package scoped as it is only extended by classes in the same package.
• Constructor for class javafx.css.converter.ShapeConverter is made private as it is a singleton class. No javadoc is needed for this simple private constructor.

Specification

 abstract public class Selector {

     /**
-     * @deprecated This constructor was exposed erroneously and will be removed in the next version. Use {@link #createSelector(String)} instead.
+     * Package scoped constructor.
      */
-    @Deprecated(since="16", forRemoval=true)
-    public Selector() {
+    Selector() {
     }


public class ShapeConverter extends StyleConverter<String, Shape> {

-    /**
-     * @deprecated This constructor was exposed erroneously and will be removed in the next version. Use {@link #getInstance()} instead.
-     */
-    @Deprecated(since="16", forRemoval=true)
-    public ShapeConverter() {
+    private ShapeConverter() {
     }