Port everything over to AsXml

parsers/src/jingle_thumnails.rs

@@ -6,12 +6,12 @@
 // License, v. 2.0. If a copy of the MPL was not distributed with this
 // file, you can obtain one at http://mozilla.org/MPL/2.0/.
 
-use xso::{FromXml, IntoXml};
+use xso::{AsXml, FromXml};
 
 use crate::ns;
 
 /// A Jingle thumbnail.
-#[derive(FromXml, IntoXml, PartialEq, Debug, Clone)]
+#[derive(FromXml, AsXml, PartialEq, Debug, Clone)]
 #[xml(namespace = ns::JINGLE_THUMBNAILS, name = "thumbnail")]
 pub struct Thumbnail {
     /// The URI of the thumbnail.