smack-websocket would be a great addition, as long as it's based on draft-ietf-xmpp-websocket-10 (I assume dele's openfire-websockets does so).
Tyrus seems to be a good choice. Important for smack-websocket would be Android (API 8) support, which means that every API it depends on (e.g. Tyrus) must also support running on Android API 8. There are a few hints that Tyrus seems to be able to run on Android, but there is no min SDK level mentioned:
[TYRUS-256] Support Client API on Andriod - Java.net JIRA
https://blogs.oracle.com/PavelBucek/entry/websocket_client_on_android_tyrus
POC code is great as first step, but in order to get smack-websocket merged I expect good quality code preferable with some unit tests. This may take a few review rounds and coordination with me. But if you are willing and motivated to drive this project I would support you wherever I can. I invite you to join #smack (Freenode) to talk about the next steps (and of course to idle around ).