Remove leading '/' from target paths.

This is inappropriate on Windows, and breaks non-prefix builds there.

This is only needed when we calculate a relative path from a sysroot,
so only add it in that case.

Task-number: QTBUG-34880
Change-Id: I0e3b3d977a7b56649e4ba0077ac574aabf1dc915
Reviewed-by: Oswald Buddenhagen <oswald.buddenhagen@digia.com>
Reviewed-by: Stephen Kelly <stephen.kelly@kdab.com>
QNX: Fix retrieving the window group name

The code assumes that there is a root window, and crashed
otherwise.

Task-number: QTBUG-35121
Change-Id: Idbf0e0bfc03cd427f0aab81db88b34fe94228c81
Reviewed-by: Rafael Roquetto <rafael.roquetto@kdab.com>
Revert "Store the font's scalability in QFontEngine."

This reverts commit 65b12fbdb13d34c61bcadd5cc8fd6ee28a8dfafd.

QFontEngine is not always loaded from QFontDatabase, resulting in
the flag not being set.

Change-Id: I39bc5bd4a8dea153d191cfc55f4324195f75f64c
Reviewed-by: Konstantin Ritt <ritt.ks@gmail.com>
Reviewed-by: Mitch Curtis <mitch.curtis@digia.com>
Reviewed-by: Lars Knoll <lars.knoll@digia.com>