RFR (XS): 8150085: Convert TraceClearedExceptions to Unified Logging

[Rachel Protacio]

Hi,

Please review this change, converting -XX:+TraceClearedExceptions to 
-Xlog:exceptions=debug. (This change replaces the one I sent out earlier 
that was going to delete the option.)

Bug: https://bugs.openjdk.java.net/browse/JDK-8150085
Open webrev: http://cr.openjdk.java.net/~rprotacio/8150085.02/

Passes JPRT; if you'd like to see additional testing, please let me know.

Thank you,
Rachel