Summary: Add G1BiasedArray<T> that is an array where each element represents a fixed-sized subdivision of the heap. Use this abstraction to refactor the HeapRegionSeq class.
Reviewed-by: brutisso

Reviewed-by: kvn, coleenp

Summary: Change the type of fields / variables / etc. that represent region counts and indeces from size_t to uint.
Reviewed-by: iveresov, brutisso, jmasa, jwilhelm

Summary: Extend the jmap -heap output for G1 to include some more G1-specific information.
Reviewed-by: brutisso, johnc, poonam

Summary: Declare GrainBytes, GrainWords, and CardsPerRegion as size_t.
Reviewed-by: jcoomes, tonyp, jmasa

Reviewed-by: brutisso, johnc

Summary: Extend the SA to recognize the G1CollectedHeap and implement any code that's needed by our serviceability tools (jmap, jinfo, jstack, etc.) that depend on the SA.
Reviewed-by: never, poonam, johnc