Tests: restart the action manager between tests.

Original commit: elastic/x-pack-elasticsearch@73bc51717b

src/main/java/org/elasticsearch/alerts/AlertManager.java

@@ -216,9 +216,9 @@ public class AlertManager extends AbstractComponent {
      * For testing only to clear the alerts and actions between tests.
      */
     public void clear() {
-        scheduler.clearAlerts();
+        scheduler.clear();
         alertsStore.clear();
-        actionManager.clear();
+        actionManager.restart();
     }
 
     private void internalStop() {

src/main/java/org/elasticsearch/alerts/AlertsStore.java

@@ -140,7 +140,7 @@ public class AlertsStore extends AbstractComponent {
     }
 
     /**
-     * Clears the in-memory representation of the alerts
+     * Exists for testing purposes
      */
     public void clear() {
         alertMap.clear();

src/main/java/org/elasticsearch/alerts/actions/AlertActionManager.java

@@ -135,8 +135,12 @@ public class AlertActionManager extends AbstractComponent {
         return started.get();
     }
 
-    public void clear() {
-        actionsToBeProcessed.clear();
+    /**
+     * Exists for testing purposes.
+     */
+    public void restart() {
+        stop();
+        doStart();
     }
 
     private void doStart() {

src/main/java/org/elasticsearch/alerts/scheduler/AlertScheduler.java

@@ -98,7 +98,10 @@ public class AlertScheduler extends AbstractComponent {
         }
     }
 
-    public void clearAlerts() {
+    /**
+     * Exists for testing purposes
+     */
+    public void clear() {
         try {
             if (scheduler != null) {
                 scheduler.clear();