[ACS-1291] Asynchronous mechanism to send events (#351)

* Performance optimisation spike

* Event2 is now sending event asynchronously

* Now forcing synchronous calls in tests for events2

* Now qualifying the event service used in tests

Co-authored-by: Nana Insaidoo <insaidoo.nana@yahoo.it>

repository/src/test/java/org/alfresco/repo/event2/AbstractContextAwareRepoEvent.java

@@ -31,6 +31,7 @@ import static org.awaitility.Awaitility.await;
 
 import java.util.ArrayList;
 import java.util.List;
+import java.util.concurrent.Executor;
 
 import javax.jms.ConnectionFactory;
 
@@ -104,6 +105,10 @@ public abstract class AbstractContextAwareRepoEvent extends BaseSpringTest
     @Autowired
     protected ObjectMapper event2ObjectMapper;
 
+    @Autowired @Qualifier("eventGeneratorV2")
+    protected EventGenerator eventGenerator;
+
+
     protected NodeRef rootNodeRef;
 
     @BeforeClass
@@ -143,6 +148,18 @@ public abstract class AbstractContextAwareRepoEvent extends BaseSpringTest
         });
     }
 
+    @Before
+    public void forceEventGeneratorToBeSynchronous() {
+        eventGenerator.setThreadPoolExecutor(new Executor()
+        {
+            @Override
+            public void execute(Runnable command)
+            {
+                command.run();
+            }
+        });
+    }
+
     @After
     public void tearDown()
     {