the id for the new stream. If %NULL, a new one will be automatically generated
the #GstCaps of the stream
the #GstStreamType of the stream
the #GstStreamFlags of the stream
Return: The new #GstStream
ConstructionException GTK+ fails to create the object.
1.10
Create a new #GstStream for the given @stream_id, @caps, @type and @flags