code review request, CR 7166885 X509CRLEntryImpl does not handle CRLs with no extension properly

[Xuelei Fan]

Hi,

Please review the fix for a synchronization issue of JSSE.

webrev: http://cr.openjdk.java.net./~xuelei/7166885/webrev.00/

Cause of the issue: the extensions filed in a X509 CRL may be empty. For
such cases, the X509CRLEntryImpl.getExtensions() should return empty map
instead of throwing NullPointerException.

Thanks,
Xuelei