Get rid of QInputDevicePrivate::extra

Since QPA plugins own the input device objects that they create, they
can also subclass to add arbitrary extra data (as was done with
QWinTabPointingDevice in abb5f0d3768a817b7e30639107210e64b8dbc138);
so this pointer seems unnecessary.  It's unused so far AFAIK.
Retaining it also brings up the possibility of a memory leak:
~QInputDevice() doesn't delete it, and whatever code stores something
there would need to make sure it gets deleted.

Change-Id: I7ec264c23c74b83db1f37f64f31857caf551fdae
Reviewed-by: Fabian Kosmale <fabian.kosmale@qt.io>
Reviewed-by: Tor Arne Vestbø <tor.arne.vestbo@qt.io>
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@qt.io>

0 files changed, 0 insertions, 0 deletions