inetcomm: Add an implementation of IVirtualStream.

[Hans Leidekker]

On Friday 07 November 2008 13:48:29 Huw Davies wrote:
> > This interface is undocumented but fortunately its name was enough
> > of a hint to create a sensible implementation. Used by Outlook when
> > retrieving or sending a mail.
> 
> We already have MimeOleCreateVirtualStream() which is implemented on top 
> of CreateStreamOnHGlobal()...

Hmm, that may work too. I wonder if they are fully compatible though,
the Read method is called with cb set to -1, which appears to mean that
the stream size should be taken. Do you know off hand if that's supported
by IStream?

 -Hans