#A4##Persist######PersistFile##########PersistStorage##########PersistStream######load########stream##Stream######type##ContentType######save########stream##Stream######type##ContentType##########This interface is used by items which only need to store
information in a Stream (monikers are the primary users of this).
Unlike PersistStorage, the Stream passed is only valid
during these calls (ie, you should not incref these
and use them after this).##@stream: Where to load the state from
@type: the MIME content type of the data, or ""
if it is unknown.
Loads the status of the object from @stream##@stream: Where to save the state to.
@type: the MIME content type to save the data in,
or "" if any type is acceptable.
If no exception was thrown the data in the stream has
the requested content type; if no type was requested
the first entry from getContentTypes is returned.
Hence no return value is needed.
Saves the state of the object to the @stream#