[PATCH 4/5] winegstreamer: Set MF_PD_MIME_TYPE on source's presentation descriptor.

[Nikolay Sivov]

I have two concerns, or questions:

- do we always return uncompressed types from winegstreamer source? If
so won't this mime type contradict raw format that it actually returns?
- if we need to return mime attribute, is it possible to get it from
some gstreamer attribute and not from original bytestream attribute,
that occasionally we set automatically?