OPENDJ-1869 CR-6727 Fix NPE in EntryCachePreloader.EntryCacheCollector

Fabio Pistolesi

11.48.2015 d12cc90fc15f432f43abc394b4090f9b4f7b2a03

opendj-server-legacy/src/test/java/org/opends/server/extensions/PreloadEntryCacheTestCase.java does not exist in tree ca118bd60053ae74be70f03cf8dd2679accc914f