RuntimeException:ClassNotFoundException android.arch.lifecycle.ProcessLifecycleOwnerInitializer

This ended up being a multdex issue. I followed the docs here -> https://developer.android.com/studio/build/multidex.html#mdex-gradle and it works great now!

Gradle:

implementation 'com.android.support:multidex:1.0.3'

App.java:

public class App extends Application implements Application.ActivityLifecycleCallbacks {

@Override
protected void attachBaseContext(Context base) {
    super.attachBaseContext(base);
    MultiDex.install(this);
}

All I had to do was add the following to my proguard-rules.pro file:

-keep class android.arch.lifecycle.** {*;}

In my case, Somehow android architecture lifecycle files getting omitted with Android bundle on Pie(Android9). So what I did was added keep statement for the same in proguard-rules.pro

For AndroidX :

-keep class androidx.lifecycle.** {*;}

For Support :

-keep class android.arch.lifecycle.** {*;}