locking maps for entire GetNewOrUsedClass() process. locking maps while trying to Find an IID off of a Root. locking when removing from RealObjectToProxyObjectMap I am hoping that this will fix some of the SMP problems, namely 21556. r=mccabe. git-svn-id: svn://10.0.0.236/trunk@57484 18797224-902f-48f8-a5cc-f745e15eee43