RFR: 8176717: GC log file handle leaked to child processes

[Leo Korinth]

> New webrev (only change is removing module-info.java change):
> http://cr.openjdk.java.net/~lkorinth/8176717/01/
> 
> Thanks,
> Leo

Hi! (again)

I would like more feedback on my change. Thomas Stüfe has proposed some 
changes (including maybe rename os::fopen_retain and/or possibly move it 
away from os).

I feel it is vital to have a hotspot-wide wrapper function for fopen. 
More so if core libs can not fix the problem due to legacy concerns. In 
the long run all "open" operations ought to be handled by wrappers --- 
in my opinion.

I need help to get a solution that is to your satisfaction; so please 
continue the discussion that Thomas Stüfe started! When we agree on a 
solution, I will also create a bug on core-libs to fix the TRUE on 
inherits system handles (or document the reason for why it ought to be 
TRUE).

Thanks,
Leo