Marks the cell as being non-sparse. Some table models allow sparse markup, where some cells of a table are not explicitly described in markup. Arbortext Editor and Arbortext Editor add generated cell markup to the document when reading a sparse table so that there is markup underlying every table cell. When a document containing a table is saved, this generated markup is deleted, unless the cell has acquired content, attributes, or some other reason for existence. This function allows the user to require that the markup corresponding to a cell NOT be discarded, even if it is generated markup.