Pls review (S) 7117389: Add a framework for vendor-specific command line switch extensions to Hotspot

[Paul Hohensee]

Webrev here:

http://cr.openjdk.java.net/~phh/7117389/

This webrev defines and uses, but does not implement, a switch extension 
interface.

I've added a new file, globals_ext.hpp, that contains hooks for 
vendor-specific additions
to the set of Hotspot command line switches and added their use to 
globals.hpp,
globals.cpp and globals_extension.hpp.  I chose "_ext" as a generic 
suffix for files
containing extension hooks.  In effect, such files are interface 
definitions.  A vendor
supplies a file, perhaps of the same name in another source base (as can 
be seen in
the Hotspot makefiles), that implements the extension hooks.

Thanks,

Paul