The Jitsi team would like to thank @AliKarpuzoglu, @linuxpi and The Hopp Foundation for the initial effort and help throughout.

Co-authored-by: Saúl Ibarra Corretgé <saghul@jitsi.org>
Co-authored-by: zycwind <391321232@qq.com>

This only works automatically on Android >= 8. On other platforms / versions, it
relies on the SDK user on implementing a "reduced UI" mode and reacting to the
"request PIP" delegate method.