Flutter enables minification for every release build, and nothing but a
keep rule reaches androidx.media3.decoder.ffmpeg. DefaultRenderersFactory
instantiates FfmpegAudioRenderer with Class.forName, media3's consumer
rules only -keepclassmembers its constructor, and this project had no
proguard-rules.pro at all, so R8 shrank the renderer out of the shipped
dex and the reflective lookup failed with ClassNotFoundException. The
same pass dropped FfmpegAudioDecoder.growOutputBuffer, which ffmpeg_jni
resolves in JNI_OnLoad and whose absence fails the whole
System.loadLibrary("ffmpegJNI") call.
Release builds therefore lost every codec that decoder adds. TrueHD and
DTS-HD fell through to MediaCodecAudioRenderer, which has no decoder for
them, so a 4K Dolby Vision file died with NO_SUITABLE_DECODER_ERROR and
handed off to the mpv fallback — losing ExoPlayer's Profile 7 to 8.1
conversion on hardware that could have direct-played it. Only debug
builds, where R8 never runs, exercised the working path.
Keep the package and the type named in the JNI callback descriptor, and
guard the invariant so it cannot silently rot again: check_shrinker_rules
fails when an app class in a reflected namespace, a FindClass target, a
native callback member, or a descriptor type has no keep covering it.
Also record the built audio renderers, because whether the extension
loaded is otherwise indistinguishable in an uploaded log.
close#1703
edde746