[8u40] RFR: RT-39571: [Mac] AVFoundation player never sends FINISHED state at end of stream

[David DeHaven]

Kevin, Kirill, please review the following change for 8u40

JIRA Issue:
https://javafx-jira.kenai.com/browse/RT-39571

Webrev:
http://cr.openjdk.java.net/~ddehaven/RT-39571/rt.0/

-DrD-