Passwords: Support the pre-4.3 behavior of `wp_new_user_notification()`.

Hello, it's me again. A pluggable function named `wp_new_user_notification()`. A few months ago, after [33023], I have lost my second parameter `$plaintext_pass`. But thanks to [33620] I got a new one.
Bad idea - It hasn't had the same behavior as my previous parameter.
To solve that the second parameter got deprecated and reintroduced as the third parameter in [34116]. I was happy again, for a short time.
You remember my lost friend `$plaintext_pass`? No? Well, if its value was empty no notification was sent to the user. This behavior was still lost. And that's what this change is about: Don't notify a user if a plugin uses `wp_new_user_notification( $user_id )`.

You're asking if I'm happy now? Dunno, but maybe you have learned something about pluggable functions, have you?

Props danielbachhuber.
Fixes #34377.
Built from https://develop.svn.wordpress.org/trunk@35735


git-svn-id: http://core.svn.wordpress.org/trunk@35699 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-includes/pluggable.php

@@ -1458,7 +1458,7 @@ function wp_notify_postauthor( $comment_id, $deprecated = null ) {
 	// we want to reverse this for the plain text arena of emails.
 	$blogname = wp_specialchars_decode(get_option('blogname'), ENT_QUOTES);
 	$comment_content = wp_specialchars_decode( $comment->comment_content );
-	
+
 	switch ( $comment->comment_type ) {
 		case 'trackback':
 			$notify_message  = sprintf( __( 'New trackback on your post "%s"' ), $post->post_title ) . "\r\n";
@@ -1737,8 +1737,7 @@ if ( !function_exists('wp_new_user_notification') ) :
  * @param int    $user_id    User ID.
  * @param null   $deprecated Not used (argument deprecated).
  * @param string $notify     Optional. Type of notification that should happen. Accepts 'admin' or an empty
- *                           string (admin only), or 'both' (admin and user). The empty string value was kept
- *                           for backward-compatibility purposes with the renamed parameter. Default empty.
+ *                           string (admin only), or 'both' (admin and user). Default empty.
  */
 function wp_new_user_notification( $user_id, $deprecated = null, $notify = '' ) {
 	if ( $deprecated !== null ) {
@@ -1758,7 +1757,8 @@ function wp_new_user_notification( $user_id, $deprecated = null, $notify = '' )
 
 	@wp_mail(get_option('admin_email'), sprintf(__('[%s] New User Registration'), $blogname), $message);
 
-	if ( 'admin' === $notify || empty( $notify ) ) {
+	// `$deprecated was pre-4.3 `$plaintext_pass`. An empty `$plaintext_pass` didn't sent a user notifcation.
+	if ( 'admin' === $notify || ( empty( $deprecated ) && empty( $notify ) ) ) {
 		return;
 	}
 

wp-includes/version.php

@@ -4,7 +4,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '4.4-beta4-35734';
+$wp_version = '4.4-beta4-35735';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.