RFR (S): JDK-8006432 - Ratio flags should be unsigned

[Jesper Wilhelmsson]

Hi,

I'm looking for a couple of reviews for this small change.

Bug: JDK-8006432 - Ratio flags should be unsigned

Webrev:
http://cr.openjdk.java.net/~jwilhelm/8006432/webrev/

Summary:
Four flags whose contents are assumed to be unsigned were stored in 
signed variables. I have changed these to be unsigned instead.

Testing:
Manual testing and JPRT.

/Jesper