Summary: Refactor test/sun/tools/common/* code and refactor AnonLoggerWeakRefLeak and LoggerWeakRefLeak to use it.
Reviewed-by: ohair, alanb

Summary: Use ReferenceQueues to manage WeakReferences in LogManager and Logger.
Reviewed-by: dholmes, alanb, emcmanus, tonyp
Contributed-by: jeremymanson@google.com