Media: Sanitize upload filename.

Merge of [38538] to the 4.4 branch.

Built from https://develop.svn.wordpress.org/branches/4.4@38541


git-svn-id: http://core.svn.wordpress.org/branches/4.4@38484 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-admin/includes/media.php

@@ -286,7 +286,7 @@ function media_handle_upload($file_id, $post_id, $post_data = array(), $override
 	$url = $file['url'];
 	$type = $file['type'];
 	$file = $file['file'];
-	$title = $name;
+	$title = sanitize_title( $name );
 	$content = '';
 	$excerpt = '';