Synopsis
Provides a Views argument handler which accepts an entity ID: it assumes this entity ID is the same entity type as the base_table
of the current view. If it notices the ID passed in the argument matches the ID of a row in the results, it adds an HTML data-views-mark-current="current-entity--row"
attribute to the row; and an HTML data-views-mark-current="current-entity--field"
attribute to each field in the row.