[PATCH 1/6] winegstreamer: Insert videoconvert into decoded-video streams.

[Derek Lesho]

> You could probably avoid this sort of thing by just calling
> MFCreateStreamDescriptor() inside of the if/else switch.
I decided against doing this in v2 of the patch, since it would require 
adding more cleanup code inside the branches; either through a second 
goto or copying heap_free to three failure paths.