TypeDetection::queryTypeByDescriptor() adds the FilterName property to
the MediaDescriptor, use that if present.

Strangely enough the sequence returned by XNameAccess::getByName(sType)
of the type detection contains an empty PreferredFilter value so that is
useless in this scenario.

Change-Id: I5cdc9fe71e35bdb7c511739c7f7728134941649a