API CHANGE: unpublish com.sun.star.document.MediaDescriptor.

This is a service that basically describes the properties passed to
loadComponentFromURL and possibly other load/save related APIs.  As
some properties get deprecated (some already have), new ones added as
the loading processs gets re-worked (including the type detection
process), we need the flexibility to change its property set.

Since all properties described here are optional, leaving it published
would make little sense.

Change-Id: I59384e62c7b6ab5c599141c8fc73a37c8bfe56e7

offapi/com/sun/star/document/MediaDescriptor.idl

@@ -53,7 +53,7 @@ module com { module sun { module star { module document {
 
     @see com::sun::star::beans::PropertyValue
  */
-published service MediaDescriptor
+service MediaDescriptor
 {
     /** May be set by filters or detection services if user has chosen to
         abort loading/saving, e.g. while entering a password.