[ros-diffs] [fireball] 32814: - Rewrite the SD Cache functions to use the Windows 2003 structures (thanks to Alex for providing them). - Use pushlocks instead of the fast mutex that was previously used. - Improve the performance of some paths by reducing lock acquisition time, and using atomic operations instead when possible. - Implement the exported Ob APIs which were added in Windows XP to access the Sd cache (ObReference/DereferenceSecurityDescriptor and ObLogSecurityDescriptor). These are used by file