The immutable empty stack now implemnts equals() and hashCode().

git-svn-id: https://svn.apache.org/repos/asf/logging/log4j/log4j2/trunk@1595910 13f79535-47bb-0310-9956-ffa450edef68
org.apache.logging.log4j.core.LogEvent.getContextStack() never returns null (again, the Flume case is special).

git-svn-id: https://svn.apache.org/repos/asf/logging/log4j/log4j2/trunk@1595911 13f79535-47bb-0310-9956-ffa450edef68
Organize imports per new guidelines.

git-svn-id: https://svn.apache.org/repos/asf/logging/log4j/log4j2/trunk@1595914 13f79535-47bb-0310-9956-ffa450edef68
Redundant null check: The variable localParents cannot be null at this location.

git-svn-id: https://svn.apache.org/repos/asf/logging/log4j/log4j2/trunk@1595915 13f79535-47bb-0310-9956-ffa450edef68
Statement unnecessarily nested within else clause.

git-svn-id: https://svn.apache.org/repos/asf/logging/log4j/log4j2/trunk@1595920 13f79535-47bb-0310-9956-ffa450edef68
Statement unnecessarily nested within else clause.

git-svn-id: https://svn.apache.org/repos/asf/logging/log4j/log4j2/trunk@1595921 13f79535-47bb-0310-9956-ffa450edef68
Statement unnecessarily nested within else clause.

git-svn-id: https://svn.apache.org/repos/asf/logging/log4j/log4j2/trunk@1595923 13f79535-47bb-0310-9956-ffa450edef68
Statement unnecessarily nested within else clause.

git-svn-id: https://svn.apache.org/repos/asf/logging/log4j/log4j2/trunk@1595925 13f79535-47bb-0310-9956-ffa450edef68
Statement unnecessarily nested within else clause.

git-svn-id: https://svn.apache.org/repos/asf/logging/log4j/log4j2/trunk@1595926 13f79535-47bb-0310-9956-ffa450edef68