Througout the initial review the singleton was transformed into an
ordinary class, but a error was introduced: The "reference" file was
incorrectly assumed to be the editors file, which is wrong, since
it should be the declaration file.

Change-Id: Iad3e25a690fa8bd07a18184b24b10f8dea965332
Reviewed-by: Roberto Raggi <roberto.raggi@nokia.com>