Phonon MMF: artefacts are visible during redrawing of video widget

Device: Nokia 5800
Firmware version: 40.0.001
Release: 5695b50d
Platform: armv5 udeb
Compiler used: RVCT 2.2 build 686
Application: qmediaplayer
Launched from: application launcherarmv
Problem description:
Select 'Open File' and then select a video file. Watch the app UI in the period between the file dialog being dismissed and the video starting to play. Artefacts are visible as the app layout changes, and the video widget is consequently resized.

Similar artefacts are visible during full-screen transitions (both directions), and when screen orientation is changed.

This is a consequence of the use of the disableBlit flag in Phonon::MMF::VideoOutput. This is necessary in order for video to be visible, but at present, blitting is disabled too early - it should happen immediately before the MMF stack writes to the UI framebuffer.