Review request for 8035807: Convert use of sun.misc.BASE64Encoder/Decoder with java.util.Base64

[Mandy Chung]

https://bugs.openjdk.java.net/browse/JDK-8035807

Webrev at:
http://cr.openjdk.java.net/~mchung/jdk9/webrevs/8035807/webrev.00/

This patch converts the last 2 references to 
sun.misc.BASE64Encoder/Decoder from the jdk repo with 
java.util.Base64.   We should also update the tests and I have filed 
JDK-8037873 for that.

Thanks
Mandy