Release builds aborted on the first callback of every test:
NoSuchMethodError: no non-static method "Lp0;.onOutput(Ljava/lang/String;)V"
R8 had renamed MainThreadCallback to p0 along with its methods, so
GetMethodID(env, cls, "onOutput", ...) in iperf_jni.c resolved nothing. The
names are a contract between C and Kotlin that the minifier cannot see.
Adds keep rules for IperfRunner, the IperfCallback interface and — the part
that matters — everything implementing it, since the lookup happens on the
concrete object's class rather than on the interface. A general rule keeps any
class declaring a native method, so a future one is covered without a new rule.
Debug builds do not minify, which is why every on-device check so far passed
while the shipping artifact was broken. Found by running the release APK
during release preparation.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
