Ever since I upgraded to gradle 3.0 our main `Application`'s onCreate is not firing from a production-flavour app. When building for our staging flavour however, the Application's onCreate is called just fine. 

Since the Application's onCreate is never called, our `Realm` is never initialized, and the app crashes when trying to access `Realm` later.

AndroidManifest.xml: 

```
 <application
        android:name=".App"
        android:allowBackup="true"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
....

```

App.kt:

```
class App : Application() {

    override fun onCreate() {
        super.onCreate()
        Realm.init(this)
        println("This is never called")
    }
}

```

build.gradle:

```
apply plugin: 'com.android.application'
apply plugin: 'kotlin-android'
apply plugin: 'realm-android'
apply plugin: 'kotlin-android-extensions'
apply plugin: 'com.github.triplet.play'

....

android {

    flavorDimensions "testing"

    productFlavors {
        production {
            dimension "testing"
            applicationId "com.imerso.app"
        }
        staging {
            dimension "testing"
            applicationId "com.imerso.app.staging"
            externalNativeBuild {
              cmake {
                targets 'cpp_scan_app', 'unittests'
              }
            }
        }
    }

    compileSdkVersion 25
    buildToolsVersion '26.0.2'

    dexOptions {
      // Sets the maximum number of DEX processes
      // that can be started concurrently.
      maxProcessCount 8
      // Sets the maximum memory allocation pool size
      // for the dex operation.
      javaMaxHeapSize "2g"

```

....

not sure if our change to gradle 3.0 is the culprit here, but everything worked fine until I did the upgrade.