SPARK-5548: Fix for AkkaUtilsSuite failure - attempt 2

Author: Jacek Lewandowski <lewandowski.jacek@gmail.com>

Closes #4653 from jacek-lewandowski/SPARK-5548-2-master and squashes the following commits:

0e199b6 [Jacek Lewandowski] SPARK-5548: applied reviewer's comments
843eafb [Jacek Lewandowski] SPARK-5548: Fix for AkkaUtilsSuite failure - attempt 2

core/src/test/scala/org/apache/spark/util/AkkaUtilsSuite.scala

@@ -20,6 +20,7 @@ package org.apache.spark.util
 import java.util.concurrent.TimeoutException
 
 import scala.concurrent.Await
+import scala.util.{Failure, Try}
 
 import akka.actor._
 
@@ -370,8 +371,12 @@ class AkkaUtilsSuite extends FunSuite with LocalSparkContext with ResetSystemPro
     val selection = slaveSystem.actorSelection(
       AkkaUtils.address(AkkaUtils.protocol(slaveSystem), "spark", "localhost", boundPort, "MapOutputTracker"))
     val timeout = AkkaUtils.lookupTimeout(conf)
-    intercept[TimeoutException] {
-      slaveTracker.trackerActor = Await.result(selection.resolveOne(timeout * 2), timeout)
+    val result = Try(Await.result(selection.resolveOne(timeout * 2), timeout))
+
+    result match {
+      case Failure(ex: ActorNotFound) =>
+      case Failure(ex: TimeoutException) =>
+      case r => fail(s"$r is neither Failure(ActorNotFound) nor Failure(TimeoutException)")
     }
 
     actorSystem.shutdown()