RFR: 8000780 back ported Fix zero fail to build in JDK7u-dev [updated]

[Chris Phillips @ T O]

Hi

{Not sure if this needs a new bug or not, it definitely needs a sponsor
- Twisti ? }

Attached is a backport (essentially resurrection of the Permgen code)
of 8000780 now updated with Roman Kennke's comments. Checked and built
against hsx24b28. (Current jdk7u-dev hs)

Please review.

Cheers!
Chris
 PS
Webrev is here:
http://integral-portal.lgonqn.org/temp/ChrisPhi/jdk7u-dev-zero/hs24b28/