RFR: JDK-8236598: javac rejects record component with 'final' modifier

[Vicente Romero]

Hi,

Please review a simple fix to a bug in the records code. Basically the 
spec allows record components to redundantly declare the `final` 
modifier. The current implementation is not allowing this. This patch is 
fixing this issue.

Thanks,
Vicente

http://cr.openjdk.java.net/~vromero/8236598/webrev.00/
https://bugs.openjdk.java.net/browse/JDK-8236598