added maximumTouchPoints to QTouchDevice

This was missing information which the driver can provide.

Change-Id: I2574745635d6fdf608bc5617999aec46d9312c09
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@digia.com>
xcb: touchpad support

Relative touch devices tend to provide a moving point for one finger,
then when more points are pressed, the root_x/root_y stay stationary
while the Rel X/Y valuators provide info about the movements around
that point.  Synthesize moving touch points from those so that
gestures become possible.  Behavior is now similar to that on OS X.

Change-Id: I1c65fb04849d19f11c3bf166044f296d95c33da1
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@digia.com>
Reviewed-by: Frederik Gladhorn <frederik.gladhorn@digia.com>
Move the declaration of QFileIconProviderPrivate to it's own file.

Needed to backport qtbase/46685f755b01288fd53c4483cb97a22c426a57f0
to Qt4.

We can't add new symbols in Qt4 to QFileIconProvider so we will make
the private class a friend of the QFileDialog.

Change-Id: I6bc5a2d127b09f20633e733a79de509c8c186c6c
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@digia.com>
Reviewed-by: Sergio Ahumada <sergio.ahumada@digia.com>