Fix https://issues.apache.org/bugzilla/show_bug.cgi?id=56784
Fix a couple of rare but theoretically possible atomicity bugs.

git-svn-id: https://svn.apache.org/repos/asf/tomcat/trunk@1615942 13f79535-47bb-0310-9956-ffa450edef68
Simplify catch block
Enable Tomcat to start when using SSL with an IBM JRE in strict SP800-131a mode.

git-svn-id: https://svn.apache.org/repos/asf/tomcat/trunk@1615947 13f79535-47bb-0310-9956-ffa450edef68