Notify the trash can that an XContent is deleting itself
into it.
Parameter Properties
The trash can uses this interface to access the properties of the
content being deleted, to copy them for later display etc. The
trash can will not use the interface after it has returned from this
method.
Parameter Identifier
When the deleted content is later restored or ultimately deleted, the
trash can will use this identifier to query an XContent that it will
send the undelete or delete command to.
