Espresso.onIdle() crashing in base.UiControllerImpl$MainThreadInterrogation.execCount

We get this random crash from an IdlingResource called from a Kotlin Instrumented Test:

java.lang.RuntimeException: java.util.concurrent.ExecutionException: java.lang.NullPointerException: Attempt to read from field 'int androidx.test.espresso.base.UiControllerImpl$MainThreadInterrogation.execCount' on a null object reference
at androidx.test.espresso.Espresso.onIdle(Espresso.java:342)

I'm afraid there is no easy repro, as it's happening at random when running our instrumented test suite on an LG G6 (LG-H870 - 8.0.0) running Android 8.0 from Jenkins.

We are building with:
androidTestImplementation "androidx.test.espresso:espresso-core:3.2.0"
androidTestImplementation "androidx.test.espresso:espresso-contrib:3.2.0"

Start with the stack trace at Espresso.onIdle(Espresso.java:342) and inspect UiControllerImpl$MainThreadInterrogation.execCount in Espresso 3.2.0. Try to reproduce the intermittent crash in the Kotlin instrumented test suite on Android 8.0, then verify that onIdle no longer crashes under the reported conditions.

Written by the indexing model from the issue text.