Request for review: 7039182 NIO platform specific files

[Alan Bateman]

David Holmes wrote:
> http://cr.openjdk.java.net/~dholmes/7039182/webrev/
>
> This will be pushed through the TL jdk repo but Alan suggested getting 
> build-dev to review (in addition to himself).
Yes, I suggested including build-dev as Kelly asked to be included on 
any build changes.

The approach looks fine to me. If we add any new constants then the 
cross-compile build will fail, exactly what you want. Same thing if 
someone attempts to cross compile to a new target. We should rename 
NIO_PLATFORM_CLASSES_ROOT_DIR to something more generic if needed in 
other areas of the build.

-Alan.