RFR(S): 8166910, 8166911: Convert TestNewSize_test and TestOldSize_test to GTest

[Kirill Zhaldybin]

Dear all,

Could you please review this fix for 8166910 and 8166911?

Changes:
1. All asserts changed to GTest's
2. The test separated to 4 scenarios.
3. Since the initial internal test could (and actually did) impact other 
tests I moved test scenarios which use FLAG_SET_CMDLINE to other vm. 
Otherwise even after successful execution running the same test again 
caused failure.
4. Flag storage changed to new nice FLAG_GUARD macros.
5. The test deeply refactored from straight scenarios to the series of 
executors and test wrapper which runs them.

WebRev: http://cr.openjdk.java.net/~kzhaldyb/webrevs/JDK-8166910/webrev.00/

CR: https://bugs.openjdk.java.net/browse/JDK-8166910
       https://bugs.openjdk.java.net/browse/JDK-8166911

Thank you.

Regards, Kirill