RFR [15] 8244342: Compilation warnings about unexpected serialization related method signatures.

[Joe Wang]

Hi,

Please review a fix for the compilation warnings. Thanks Roger for the 
detailed instructions! If you could verify the fix with the 
work-in-progress processor, that would be great too. Regular build and 
test passed.

https://bugs.openjdk.java.net/browse/JDK-8244342
http://cr.openjdk.java.net/~joehw/jdk15/8244342/webrev/

Thanks,
Joe