RFR (XS) 8065096: java.net.Authenticator.theAuthenticator should be properly synchronized

[Aleksey Shipilev]

Hi,

Please review and commit this trivial change:
 http://cr.openjdk.java.net/~shade/8065096/webrev.01/
 https://bugs.openjdk.java.net/browse/JDK-8065096

"volatile" should nominally fix the the data race on theAuthenticator field.

Thanks,
-Aleksey.