[TEST] Reenable threadleak filters with 5 sec. lingering

src/test/java/org/elasticsearch/test/ElasticsearchTestCase.java

@@ -67,6 +67,7 @@ import static org.elasticsearch.test.hamcrest.ElasticsearchAssertions.assertAllS
  */
 @ThreadLeakFilters(defaultFilters = true, filters = {ElasticsearchThreadFilter.class})
 @ThreadLeakScope(Scope.SUITE)
+@ThreadLeakLingering(linger = 5000) // 5 sec lingering
 @TimeoutSuite(millis = 20 * TimeUnits.MINUTE) // timeout the suite after 20min and fail the test.
 @Listeners(LoggingListener.class)
 public abstract class ElasticsearchTestCase extends AbstractRandomizedTest {

src/test/java/org/elasticsearch/test/ElasticsearchThreadFilter.java

@@ -52,6 +52,6 @@ public final class ElasticsearchThreadFilter implements ThreadFilter {
                 || threadName.contains("Keep-Alive-Timer")) {
             return true;
         }
-        return nodePrefix.matcher(t.getName()).find() || true; // TODO disabled for now
+        return nodePrefix.matcher(t.getName()).find();
     }
 }