hg: openjfx/8u-dev/rt: 8154287: Intermittent crash when disposing MediaPlayer

[alexander.matveev at oracle.com]

Changeset: 0ec92259c735
Author:    almatvee
Date:      2016-05-10 12:40 -0700
URL:       http://hg.openjdk.java.net/openjfx/8u-dev/rt/rev/0ec92259c735

8154287: Intermittent crash when disposing MediaPlayer
Reviewed-by: kcr, ddehaven

! modules/media/src/main/native/jfxmedia/platform/gstreamer/GstAVPlaybackPipeline.cpp
! modules/media/src/main/native/jfxmedia/platform/gstreamer/GstAudioPlaybackPipeline.cpp
! modules/media/src/main/native/jfxmedia/platform/gstreamer/GstAudioPlaybackPipeline.h