own-caret in snip%

Notifies the snip that it is or is not allowed to display the caret (indicating ownership of keyboard focus) in some display. This method is not called to request that the caret is actually shown or hidden; the draw method is called for all display requests.

• (send a-snip own-caret own-it?) -> void
     own-it? : boolean

  The own-it? argument is #t if the snip owns the keyboard focus or #f otherwise.