[8u60] approval request for JDK-8068639: Make certain annotation classfile warnings opt-in

[Joseph D. Darcy]

Hello,

For your approval consideration:

JDK-8068639: Make certain annotation classfile warnings opt-in
https://bugs.openjdk.java.net/browse/JDK-8068639

Review thread for JDK 9:
http://mail.openjdk.java.net/pipermail/compiler-dev/2015-January/009226.html

Other than the copyright update, the changes apply cleanly to JDK 8u 
post patch-shuffling:

     http://cr.openjdk.java.net/~darcy/8068639.8u/

All langtools regression tests pass with the change.

(The change has also already been applied to the 7 update train.)

Thanks,

-Joe