RFR: Forward port of 8055006 - Store original value of Min/MaxHeapFreeRatio

[Jesper Wilhelmsson]

Hi,

The fix for JDK-8055006 was reviewed by several engineers and was pushed 
directly to 8u40 due to time constraints. This is a forward port to get the same 
changes into JDK 9.

There are two webrevs, one for HotSpot and one for the JDK.

The 8u40 HotSpot change applied cleanly to 9 so if this was a traditional 
backport it wouldn't require another review. But since this is a weird situation 
and I'm pushing to 9 I'll ask for reviews just to be on the safe side.
Also, the original 8u40 push contained some unnecessary changes that was later 
cleaned up by JDK-8056056. In this port to 9 I have merged these two changes 
into one to avoid introducing a known issue only to remove it again.

The JDK change is new. The makefiles differ between 8u40 and 9 and this new 
change makes use of functionality not present in 8u40. This patch was provided 
by Erik Joelsson and I have reviewed it myself, but it needs two reviews so 
another one is welcome.

Bug: https://bugs.openjdk.java.net/browse/JDK-8055006

Webrevs: http://cr.openjdk.java.net/~jwilhelm/8055006/jdk9/


8u40 Webrevs: http://cr.openjdk.java.net/~jwilhelm/8055006/

8u40 changes:
http://hg.openjdk.java.net/jdk8u/jdk8u-dev/hotspot/rev/f933a15469d4
http://hg.openjdk.java.net/jdk8u/jdk8u-dev/jdk/rev/312152328471

Bug and change for the second 8u40 fix:
https://bugs.openjdk.java.net/browse/JDK-8056056
http://hg.openjdk.java.net/jdk8u/hs-dev/hotspot/rev/9be4ca335650

Thanks!
/Jesper