PrivateSyncTest$privateSync instrumented test is failing on API 23

[sdsantos]

Functionality is working on the actual app, but the instrumented test is failing on API 23 and lower. The error stack trace is:

java.lang.NoSuchMethodError: No virtual method getAndSetObject(Ljava/lang/Object;JLjava/lang/Object;)Ljava/lang/Object; in class Lsun/misc/Unsafe; or its super classes (declaration of 'sun.misc.Unsafe' appears in /system/framework/core-libart.jar)
at com.google.common.util.concurrent.AbstractFuture$UnsafeAtomicHelper.gasWaiters(AbstractFuture.java:1394)
at com.google.common.util.concurrent.AbstractFuture.releaseWaiters(AbstractFuture.java:1110)
at com.google.common.util.concurrent.AbstractFuture.complete(AbstractFuture.java:1000)
at com.google.common.util.concurrent.AbstractFuture.set(AbstractFuture.java:783)
at com.google.common.util.concurrent.SettableFuture.set(SettableFuture.java:49)
at io.grpc.internal.ServerImpl$ServerTransportListenerImpl$1MethodLookup.runInternal(ServerImpl.java:559)
at io.grpc.internal.ServerImpl$ServerTransportListenerImpl$1MethodLookup.runInContext(ServerImpl.java:529)
at io.grpc.internal.ContextRunnable.run(ContextRunnable.java:37)
at io.grpc.internal.SerializingExecutor.run(SerializingExecutor.java:133)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1113)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:588)
at java.lang.Thread.run(Thread.java:818)