RFR(S) 8212127: Cleanup TLAB fast refill statistics, perf counters and etc.

[zgu at redhat.com]

Thanks, Per.
> Thanks for cleaning this up. GC changes look good. Just one minor
> thing, 
> please align the assignment here:
> 
> @@ -147,8 +145,7 @@
> 
>   void ThreadLocalAllocBuffer::reset_statistics() {
>     _number_of_refills = 0;
> -  _fast_refill_waste = 0;
> -  _slow_refill_waste = 0;
> +  _refill_waste = 0;
>     _gc_waste          = 0;
>     _slow_allocations  = 0;
>     _allocated_size    = 0;
> 
> 
Updated: http://cr.openjdk.java.net/~zgu/JDK-8212127/webrev.01/

-Zhengyu

> 
> I agree that Serviceability should ack the jstat change.
> 
> cheers,
> Per