RFR(S): 8168492: Convert CollectedHeap_test to GTest

[Igor Ignatyev]

Hi Kirill,

looks good to me.

Thanks,
— Igor 
> On Nov 1, 2016, at 5:10 PM, Kirill Zhaldybin <kirill.zhaldybin at oracle.com> wrote:
> 
> Dear all,
> 
> Could you please review this fix for 8168492?
> 
> WebRev: http://cr.openjdk.java.net/~kzhaldyb/webrevs/JDK-8168492/webrev.00/
> CR: https://bugs.openjdk.java.net/browse/JDK-8168492
> 
> Changes:
> 1. Changed _reserved to reserved_region() since _reserved is private but we already had an accessor.
> 2. Added more detailed messages for sanity checks
> 3. Otherwise pretty straight-forward conversion to gtest.
> 
> Thank you.
> 
> Regards, Kirill