dvdsubdec: Take the highlight event from the structure.
dvdsubdec: Take the highlight event from the structure.

Don't use GST_EVENT_TIMESTAMP to transfer any PTS
associated with a highlight event, instead store
it in the event structure directly, as
GstEvent::timestamp will disappear in GStreamer 2.0

https://bugzilla.gnome.org/show_bug.cgi?id=761477

GrokImageCompression/gst-plugins-ugly,StreamUtils/gst-plugins-ugly,StreamUtils/gst-plugins-ugly,GStreamer/gst-plugins-ugly,StreamUtils/gst-plugins-ugly,GStreamer/gst-plugins-ugly,GStreamer/gst-plugins-ugly,GrokImageCompression/gst-plugins-ugly,GrokImageCompression/gst-plugins-ugly