Avoid JS errors after [29057]. When the modal closes, reset the URL.

See #24716.

Built from https://develop.svn.wordpress.org/trunk@29070


git-svn-id: http://core.svn.wordpress.org/trunk@28856 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-includes/js/media-grid.js

@@ -446,6 +446,8 @@
 				this.modal.close = function() {
 					self.modal.remove();
 					$( 'body' ).off( 'keydown.media-modal' ); /* remove the keydown event */
+
+					self.resetRoute();
 				};
 
 				this.modal.content( this );