RFR: 8153583: Make OutputAnalyzer.reportDiagnosticSummary public

[Stefan Karlsson]

Hi all,

Please review this patch to make one of the testlibrary functions 
publicly accessible for tests.

http://cr.openjdk.java.net/~stefank/8153583/webrev.01
https://bugs.openjdk.java.net/browse/JDK-8153583

The reason why I need it to be public is that I want to write more 
complex verification of the the output streams, and still be able to 
call reportDiagnosticSummary when it fails. For example:

   long size = parseMemoryString(pageSizeStr);
   if (size != expectedSize) {
     output.reportDiagnosticSummary();
     throw new RuntimeException("Match from '" + pattern + "' got " + 
size + " expected: " + expectedSize);
   }

Thanks,
StefanK