Fix the bug when live streaming a MPD consists of multiple periods

Submitted by WeiChungChang

Link to original bug (#763205)

Description

Created attachment 323233
patch to fix claimed issue

Dear all:

I found that currently if a "live" DASH streaming with a MPD consists of "multiple periods", it cannot advance to next period once the we have completed the first period.

For example, in attached MPD there are 2 periods. Once we have done the first period (have played out 5 minutes content), we can never arrive the 2nd period.

It is because we never call gst_adaptive_demux_advance_period()。

[Solution]:

Once all streams have reached the end of current period & there is a next period, we should advance to next period instead of merely waiting for manifest's update.

Patch is as attached, please kindly refer to it.

Thank you~

Patch 323233, "patch to fix claimed issue":
0001-Fix-the-issue-of-live-streaming-with-multiple-period.patch