[backport] Fix shared vm code to allow zero build

[Jiri Vanek]

Hi!

I would like to offer two backports:
Originally I found them:
http://icedtea.classpath.org/hg/release/icedtea7-forest-2.4/hotspot/rev/af221c82682c
and
http://icedtea.classpath.org/hg/release/icedtea7-forest-2.4/hotspot/rev/b732355257e3

and after testing and adaptation I  used them in rpmbuilds of jdk6 with zero:
http://jvanek.fedorapeople.org/jdk6/type_hsx23_patch4.patch
and
http://jvanek.fedorapeople.org/jdk6/type_hsx23_patch3.patch

With them zero builds and works fine, without, it do not even compile.

Afaik both were pushed also to icedtea6

Are there any objections against them?
if not, I will prepare webrev (or somebody of you may directly push)


Best regards
Jiri Vanek