Deprecate php4 style constructors

PHP7 is deprecating PHP4 style constructors, so we need to modify our code to have _construct methods that fire before the named PHP4 style constructors.  The PHP4 style constructors will call the PHP5 style constructor in case it is being called directly (usually via parent::METHOD).

This modifies external libraries to add PHP5 style constructors, but doesn't add a notice for when they are used.  In WordPress core code, PHP4 style constructors are being given a call to _deprecated_constructor. To the PHP4 style constructor I say "I know that I can't take no more | It ain't no lie | I wanna see you out that door | Baby, bye, bye, bye..."

Upstream: https://wiki.php.net/rfc/remove_php4_constructors

Props jdgrimes, netweb, jorbin
See #31982



git-svn-id: https://develop.svn.wordpress.org/trunk@32990 602fd350-edb4-49c9-b593-d223f7449a82

src/wp-includes/widgets.php

@@ -173,6 +173,7 @@ class WP_Widget {
 	 * @param array  $control_options
 	 */
 	public function WP_Widget( $id_base, $name, $widget_options = array(), $control_options = array() ) {
+		_deprecated_constructor( 'WP_Widget', '4.3.0' );
 		WP_Widget::__construct( $id_base, $name, $widget_options, $control_options );
 	}
 
@@ -563,10 +564,21 @@ class WP_Widget {
 class WP_Widget_Factory {
 	public $widgets = array();
 
-	public function WP_Widget_Factory() {
+	/**
+	 * PHP5 constructor.
+	 */
+	public function __construct() {
 		add_action( 'widgets_init', array( $this, '_register_widgets' ), 100 );
 	}
 
+	/**
+	 * PHP4 constructor.
+	 */
+	public function WP_Widget_Factory() {
+		_deprecated_constructor( 'WP_Widget_Factory', '4.2.0' );
+		self::__construct();
+	}
+
 	/**
 	 * Register a widget subclass.
 	 *