[OpenJDK 2D-Dev] RFR: 8168288: Dubious FontMetrics values from NullFontScaler

[Phil Race]

Bug: https://bugs.openjdk.java.net/browse/JDK-8168288
Webrev: http://cr.openjdk.java.net/~prr/8168288/

Fixes some bizarre values you get for the "null" scaler as used
when we find we can't use the font.

More info in the bug report.

-phil.