Media: Allow multi-uploads in Galleries.

Previously, when more than one media item was uploaded using a gallery, failures occurred on the second upload.

Props glendaviesnz, Mista-Flo, hellofromTonya.
Fixes #53169.


Built from https://develop.svn.wordpress.org/trunk@51123


git-svn-id: http://core.svn.wordpress.org/trunk@50732 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-includes/js/media-views.js

@@ -5648,9 +5648,11 @@ UploaderStatus = View.extend(/** @lends wp.media.view.UploaderStatus.prototype *
 			return attachment.get('uploading');
 		});
 
-		this.$index.text( index + 1 );
-		this.$total.text( queue.length );
-		this.$filename.html( active ? this.filename( active.get('filename') ) : '' );
+		if ( this.$index && this.$total && this.$filename ) {
+			this.$index.text( index + 1 );
+			this.$total.text( queue.length );
+			this.$filename.html( active ? this.filename( active.get('filename') ) : '' );
+		}
 	},
 	/**
 	 * @param {string} filename

wp-includes/version.php

@@ -13,7 +13,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '5.8-alpha-51122';
+$wp_version = '5.8-alpha-51123';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.