RFR (XS) JDK-8164482, [REDO] G1 does not implement millis_since_last_gc which is needed by RMI GC

[Kim Barrett]

> On Sep 15, 2016, at 3:47 PM, Joseph Provino <joseph.provino at oracle.com> wrote:
> 
> Thomas, thanks!  One more review please?

src/share/vm/gc/g1/g1CollectedHeap.cpp
3154 
3155         // THIS IS ONLY HERE FOR TESTING.  IT WILL BE REMOVED BEFORE THIS FIX IS PUSHED.
3156         log_warning(gc)("millis_since_last_gc() returned: " JLONG_FORMAT,
3157             millis_since_last_gc());

Remember to take that out.

Other than that, looks good.