FakeGroupAuditService: Make audit listener members protected

The auditListeners is not used in this class, but is needed when
running tests on plugins that use audit events.

As a workaround to stop Eclipse complaining about it being unused,
change its visibility to protected. Also change the other one to
keep it consistent.

Change-Id: I5769926f4a19079e2f7cd03ca25f6152e1def063
diff --git a/java/com/google/gerrit/testing/FakeGroupAuditService.java b/java/com/google/gerrit/testing/FakeGroupAuditService.java
index 7c6674b..f2e85cd 100644
--- a/java/com/google/gerrit/testing/FakeGroupAuditService.java
+++ b/java/com/google/gerrit/testing/FakeGroupAuditService.java
@@ -35,8 +35,8 @@
 @Singleton
 public class FakeGroupAuditService implements GroupAuditService {
 
-  private final PluginSetContext<GroupAuditListener> groupAuditListeners;
-  private final PluginSetContext<AuditListener> auditListeners;
+  protected final PluginSetContext<GroupAuditListener> groupAuditListeners;
+  protected final PluginSetContext<AuditListener> auditListeners;
 
   public static class Module extends AbstractModule {
     @Override