public AsyncExecutor build() {
            return buildForScope(null);
        }
Executes an {@link RunnableEx} using a thread pool. Thrown exceptions are propagated by posting failure events.
By default, uses {@link ThrowableFailureEvent}.
<p>
Set a custom event type using {@link Builder#failureEventType(Class)}.
The failure event class must have a constructor with one parameter of type {@link Throwable}.
If using ProGuard or R8 make sure the constructor of the failure event class is kept, it is accessed via reflection.
E.g. add a rule like
<pre>
-keepclassmembers class com.example.CustomThrowableFailureEvent {
    &lt;init&gt;(java.lang.Throwable);
}
</pre>
EventBus/src/org/greenrobot/eventbus/util/AsyncExecutor.java