Print the reason why SetWindowsHookEx failed.

Task-number: QTBUG-14301
Change-Id: I4733a57034259b013864bf91aba6cce2f411ab48
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@digia.com>
Simplify mirroring code and add tests for non-aliged 1 bit images

Change-Id: I309714bc52de87c702194a4a82803d383f6ac3b3
Reviewed-by: Lars Knoll <lars.knoll@digia.com>