RFR 8215165: https://bugs.openjdk.java.net/browse/JDK-8215165

[Harold David Seigel]

Hi,

Please review this small change to improve the logging message for 
-Xlog:class+preview.

Open Webrev: 
http://cr.openjdk.java.net/~hseigel/bug_8215165/webrev/index.html

JBS Bug:  https://bugs.openjdk.java.net/browse/JDK-8215165

The fix was regression tested by running Mach5 tiers 1 and 2 tests and 
builds on Linux-x64, Windows, and Mac OS X, running tiers 3-5 tests on 
Linux-x64, and by running JCK-12 Lang and VM tests on Linux-x64.

Thanks, Harold