mpegdemux: MPEG-PS file freezes and stops on timestamp gap

Submitted by Nicola @drakkan

Link to original bug (#730566)

Description

Here is an mpeg ps file a timestamp gap:

http://195.250.34.59/temp/test.mpegps

when the overlay datetime reach 08:59:14 the timestamp go backward and gstreamer cannot play the file anymore, vlc play the file correctly until the end

you can reproduce the issue using playbin or filesrc location=... ! mpegpsdemux ! h264parse ! avdec_h264 ! xvimagesink

Version: 1.x