De-flake a test.

Author: brendandburns

extended/src/test/java/io/kubernetes/client/extended/controller/builder/DefaultControllerBuilderTest.java

@@ -183,13 +183,17 @@ public void testBuildWatchEventNotificationShouldWork() {
         };
 
     List<Request> controllerReceivingRequests = new ArrayList<>();
-    Controller testController =
+    final Semaphore latch = new Semaphore(1);
+    latch.acquire();
+
+    final Controller testController =
         ControllerBuilder.defaultBuilder(informerFactory)
             .withReconciler(
                 new Reconciler() {
                   @Override
                   public Result reconcile(Request request) {
                     controllerReceivingRequests.add(request);
+                    latch.release();
                     return new Result(false);
                   }
                 })
@@ -203,10 +207,10 @@ public Result reconcile(Request request) {
     controllerThead.submit(testController::run);
     informerFactory.startAllRegisteredInformers();
 
-    Request expectedRequest = new Request("hostname1/test-pod1");
-
-    cooldown();
+    // Wait for the request to be processed.
+    latch.acquire(1);
 
+    Request expectedRequest = new Request("hostname1/test-pod1");
     assertEquals(1, keyFuncReceivingRequests.size());
     assertEquals(expectedRequest, keyFuncReceivingRequests.get(0));