[PATCH 0/3] MR7623: Draft: winegstreamer: Use provided PTS and duration in video_decoder.

[Brendan McGrath (＠redmcg)]

This MR modifies winegstreamer to match Windows behaviour in that:
1. the video decoders will output the PTS and duration of the input sample (if provided); and
2. the WMV decoder will set any value not provided to zero

It also adds support for supplying a DTS value to the MFTs.

I've marked this as draft as it fixes the tests in MR !7563 (in addition to fixing some existing `test_wmv_decoder` tests). Also, as demonstrated in MR !7569, our demuxers output different timestamps to Windows. This change will result in those different timestamps being forwarded from the decoder. So we may also want to address that difference prior to accepting this MR.