Media Grid: use a media.view.Label instance in the toolbar for the screen reader text for Search.

See #29026.

Built from https://develop.svn.wordpress.org/trunk@29437


git-svn-id: http://core.svn.wordpress.org/trunk@29215 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-includes/media.php

@@ -2941,6 +2941,7 @@ function wp_enqueue_media( $args = array() ) {
 		'deletePermanently'      => __( 'Delete Permanently' ),
 		'apply'                  => __( 'Apply' ),
 		'filterByDate'           => __( 'Filter by date' ),
+		'searchMediaLabel'       => __( 'Search Media' ),
 
 		// Library Details
 		'attachmentDetails'  => __( 'Attachment Details' ),