AbstractMethodError after adding in-app update

Question

My app is crashing after I've added in-app updates and the play core library. Any ideas?

I'm using implementation "com.google.android.play:core:1.6.1" and the following code:

private val appUpdateManager by lazy { AppUpdateManagerFactory.create(this) }

override fun onCreate(savedInstanceState: Bundle?) {
    super.onCreate(savedInstanceState)

    appUpdateManager.appUpdateInfo.addOnSuccessListener { appUpdateInfo ->
        if (appUpdateInfo.updateAvailability() == UpdateAvailability.UPDATE_AVAILABLE
            && appUpdateInfo.isUpdateTypeAllowed(AppUpdateType.IMMEDIATE)
        ) {
            appUpdateManager.startUpdateFlowForResult(
                appUpdateInfo,
                AppUpdateType.IMMEDIATE,
                this,
                REQUEST_CODE_APP_UPDATE
            )
        }
    }
}

It crashes right away with the following exception:

2019-06-27 09:42:10.320 10700-10771/? E/AndroidRuntime: FATAL EXCEPTION: AppUpdateService
    Process: com.example.app, PID: 10700
    java.lang.AbstractMethodError: abstract method "void com.google.android.play.core.internal.n.a()"
        at com.google.android.play.core.internal.n.run(Unknown Source:0)
        at android.os.Handler.handleCallback(Handler.java:883)
        at android.os.Handler.dispatchMessage(Handler.java:100)
        at android.os.Looper.loop(Looper.java:214)
        at android.os.HandlerThread.run(HandlerThread.java:67)

---

Here's the app's build.gradle:

plugins {
    id 'com.android.application'
    id 'kotlin-android'
    id 'kotlin-android-extensions'
    id 'kotlin-kapt'
    id 'com.github.triplet.play' version '2.2.1'
    id 'realm-android'
    id 'io.fabric'
    id 'com.google.android.gms.oss-licenses-plugin'
}

if (!project.hasProperty('devBuild')) {
    apply plugin: 'com.google.firebase.firebase-perf'
}

def buildNumber = 36888

android {
    defaultConfig {
        applicationId "com.example"
        versionCode buildNumber
        versionName "1.8.11"

        resConfigs "en", "de"
        multiDexEnabled true
    }

    buildTypes {
        release {
            minifyEnabled true
            shrinkResources true
            signingConfig signingConfigs.release

            proguardFiles fileTree('./proguardrules').asList().toArray()
            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
        }

        debug {
            signingConfig signingConfigs.debug
        }
    }

    compileOptions {
        sourceCompatibility JavaVersion.VERSION_1_8
        targetCompatibility JavaVersion.VERSION_1_8
    }

    packagingOptions {
        pickFirst  'META-INF/*'
    }
}

androidExtensions {
    experimental = true
}

dependencies {
    implementation fileTree(include: ['*.jar'], dir: 'libs')

    implementation "androidx.cardview:cardview:$versions.androidx.cardview"
    implementation "androidx.constraintlayout:constraintlayout:$versions.androidx.constraint_layout"
    implementation "androidx.core:core-ktx:$versions.androidx.core_ktx"
    implementation "androidx.drawerlayout:drawerlayout:$versions.androidx.drawerlayout"
    implementation "androidx.fragment:fragment-ktx:$versions.androidx.fragment_ktx"
    implementation "androidx.lifecycle:lifecycle-livedata-ktx:$versions.androidx.lifecycle"
    implementation "androidx.lifecycle:lifecycle-viewmodel-ktx:$versions.androidx.lifecycle"
    implementation "androidx.lifecycle:lifecycle-runtime-ktx:$versions.androidx.lifecycle"
    implementation "androidx.preference:preference:$versions.androidx.preference"
    implementation "androidx.work:work-runtime-ktx:$versions.androidx.work"
    implementation "com.afollestad.material-dialogs:core:$versions.material_dialogs"
    implementation "com.afollestad.material-dialogs:input:$versions.material_dialogs"
    implementation "com.afollestad:vvalidator:$versions.vvalidator"
    implementation "com.crashlytics.sdk.android:crashlytics:$versions.crashlytics.core"
    implementation "com.google.android.material:material:$versions.androidx.material"
    implementation "com.google.android.gms:play-services-location:$versions.play_services.location"
    implementation "com.google.android.gms:play-services-maps:$versions.play_services.maps"
    implementation "com.google.android.play:core:$versions.play_services.core"
    implementation "com.google.firebase:firebase-core:$versions.firebase.core"
    implementation "com.google.firebase:firebase-config:$versions.firebase.config"
    implementation "com.google.firebase:firebase-perf:$versions.firebase.perf"
    implementation "com.xwray:groupie:$versions.groupie"
    implementation "com.xwray:groupie-kotlin-android-extensions:$versions.groupie"
    implementation "net.danlew:android.joda:$versions.joda_time_android"
    implementation "org.jetbrains.kotlin:kotlin-stdlib:$versions.kotlin.core"
    implementation "org.jetbrains.kotlinx:kotlinx-coroutines-core:$versions.kotlin.coroutines"
    implementation "org.jetbrains.kotlinx:kotlinx-coroutines-android:$versions.kotlin.coroutines"
    implementation "org.jetbrains.anko:anko-commons:$versions.anko"
    implementation "org.jetbrains.anko:anko-coroutines:$versions.anko"
}

play {
    serviceAccountCredentials = file('api-abc.json')
    defaultToAppBundles = true
    track = 'internal'
}

// Add to the bottom of the file
apply plugin: 'com.google.gms.google-services'