Fix https://issues.apache.org/bugzilla/show_bug.cgi?id=56712
Fix session time comparisons in PersistentManagerBase.
When asking for session times use internal**() methods to avoid an IllegalStateException.

Speed up TestPersistentManager test for BZ 56698 by removing sleep(1000) and fix occasional failures.

It is backport of r1609920 from tomcat/trunk.

git-svn-id: https://svn.apache.org/repos/asf/tomcat/tc7.0.x/trunk@1609924 13f79535-47bb-0310-9956-ffa450edef68