This class has documented member functions, but only the related
\headerfile was documented. The class documentation itself was
omitted with the \dontdocument command.
Replace the \headerfile with a \class command, and move the global
functions to be related to the class itself. Keep the title as a
\keyword to avoid breaking any external links. The new class page
will inherit the .html file name of the header page, so we're safe
in that regard as well.
Fixes: QTBUG-82800
Change-Id: Id51539b45e0642d91b304a37f95461ca3d6c9841
Reviewed-by: Paul Wicking <paul.wicking@qt.io>
52de905d0e