Video never recovers after a MediaCodec error #21

When MediaCodecManager.decodeFrame() catches a codec exception, it sets decoderFailed = true. After that, needCreate is always false and the decoder is not recreated until the user switches camera or leaves the app. RTP keeps flowing, so the watchdog does not reconnect either. The result is a frozen or black picture. Quad cells behave the same way.

Fix: retry decoder creation after a back-off, wait for the next SPS/IDR, and/or trigger a reconnect.