JDK 9 RFR of 8032627: Add @SuppressWarnings("serial") to appropriate javax.swing classes

[Joe Darcy]

Hello,

As part of the JDK 9 warnings cleanup, for all the javax.swing classes 
which stated

    "Serialized objects of this class will not be compatible with 
future Swing releases. ..."

I've added a @SuppressWarnings("serial") annotation if one was not 
already present:

    http://cr.openjdk.java.net/~darcy/8032627.0/

Thanks,

-Joe