[OpenJDK 2D-Dev] RFR: 8230672: Spec. for FontMetrics.getMaxAdvance is too prescriptive.

[Philip Race]

bug : https://bugs.openjdk.java.net/browse/JDK-8230672
webrev : http://cr.openjdk.java.net/~prr/8230672/

Loosen up the spec. a lot to reflect reality.

I considered deprecating the method but there isn't any easy replacement,
so it would just be annoying to old code.

This will clearly need a CSR which I will draft once we agree on the 
text here.

-phil.