Trim empty lines. Nothing but newline.

git-svn-id: https://develop.svn.wordpress.org/trunk@5700 602fd350-edb4-49c9-b593-d223f7449a82

wp-mail.php

@@ -117,7 +117,7 @@ for ($i=1; $i <= $count; $i++) :
 		$content = strip_tags($content[1], '<img><p><br><i><b><u><em><strong><strike><font><span><div>');
 	}
 	$content = trim($content);
-	
+
 	if (stripos($content_transfer_encoding, "quoted-printable") !== false) {
 		$content = quoted_printable_decode($content);
 	}