Summary:
To have touch events working we need to do memory layout changes on the
xcb events. This is fine for identifying the touch events which should
trigger the screen edge. But when passed on to Qt to have QtQuick windows
(e.g. Alt+Tab) handle the touch events, this results in a problem:
Qt itself does also the memory movement and then the movement is double
and touch events break.
To prevent this problem an RAII class is added which moves the memory in
the ctor and moves it back in the dtor. So during KWin's processing it
has the right memory layout and later on in Qt's processing it has the
proper "wrong" layout which Qt can fix again.
Test Plan: Touch events in Alt+Tab work
Reviewers: #kwin, #plasma
Subscribers: plasma-devel, kwin
Tags: #kwin
Differential Revision: https://phabricator.kde.org/D5549
014afe1c05