Index: wp-includes/media-template.php
===================================================================
--- wp-includes/media-template.php	(revision 28868)
+++ wp-includes/media-template.php	(working copy)
@@ -161,7 +161,7 @@
 	<script type="text/html" id="tmpl-uploader-inline">
 		<# var messageClass = data.message ? 'has-upload-message' : 'no-upload-message'; #>
 		<# if ( data.canClose ) { #>
-		<button class="close dashicons dashicons-no"><span class="screen-reader-text">Close overlay</span></button>
+		<button class="close dashicons dashicons-no"><span class="screen-reader-text"><?php _e( 'Close overlay' ); ?></span></button>
 		<# } #>
 		<div class="uploader-inline-content {{ messageClass }}">
 		<# if ( data.message ) { #>