RFR(XS) : 8178727: CTW should provide class names in error messages

[Igor Ignatyev]

http://cr.openjdk.java.net/~iignatyev//8178727/webrev.00/index.html
> 14 lines changed: 5 ins; 1 del; 8 mod;

Hi all,

could you please review this small enchantment for CTW test runner?
Currently, error messages contain only index of class which caused an error, which is not informative enough. this fix adds a class name to an error message.
Without the fix, errors look like:
> java.lang.Error: modules_0: failed during compilation of class #4795 
> 	at sun.hotspot.tools.ctw.CtwRunner.startCtwforAllClasses(CtwRunner.java:133) 
> 	at sun.hotspot.tools.ctw.CtwRunner.run(CtwRunner.java:78) 
> 	at sun.hotspot.tools.ctw.CtwRunner.main(CtwRunner.java:56) 
> ...
With the fix:
> java.lang.Error: modules_0: failed during compilation of class #4795:sun/reflect/misc/ReflectUtil
> 	at sun.hotspot.tools.ctw.CtwRunner.startCtwforAllClasses(CtwRunner.java:134)
> 	at sun.hotspot.tools.ctw.CtwRunner.run(CtwRunner.java:79)
> 	at sun.hotspot.tools.ctw.CtwRunner.main(CtwRunner.java:57)
> ...



webrev: http://cr.openjdk.java.net/~iignatyev//8178727/webrev.00/index.html
JBS: https://bugs.openjdk.java.net/browse/JDK-8178727
testing: hotspot/test/applications/ctw/Modules.java

Thanks,
-- Igor