RFR (S): 7095194: G1: HeapRegion::GrainBytes, GrainWords, and CardsPerRegion should be size_t

[John Cuthbertson]

Hi Everyone,

Can I have a couple of volunteers review these changes? The webrev can 
be found at: http://cr.openjdk.java.net/~johnc/7095194/webrev.0/

Background: As part of the review comments for 7092245, someone 
suggested that a better solution might be to declare 
HeapRegion::GrainBytes as a size_t. I went with the original and smaller 
fix to make it easier to back port the fix into hs22. These changes 
address that review comment - namely declare GrainBytes (and by 
extension GrainWords and CardsPerRegion) as a size_t.

Testing: the GC test suite and jprt.

Thanks,

JohnC