bab29dd76 changed scroll event handling to update
the keyboard modifier state during scroll event streams
and brought back the bug where Qt Creator would suddenly
change the font size if you pressed the command key
while scrolling.
Use momemtumPhase to detect scroll event streams.
momemtumPahse will be NSEventPhaseNone as long as there
are fingers on the trackpad. After liftoff it will
have a different value, and at this point we freeze
the keyboard modifier state until the scroll event
stream has ended.
This approach does not interfere with normal mouse
scroll wheels since momentumPhase is PahseNone for all
such scroll events.
Change-Id: I668ade8e794a97491487c9465366a316a7d6a9c8
Reviewed-by: Gabriel de Dietrich <gabriel.dedietrich@digia.com>
29585ec3d3