Bug#477331: libcairo-directfb2-udeb: Broken screen repainting in Debian Installer

[Frans Pop <elendil@planet.nl>]

Package: libcairo-directfb2-udeb
Version: 1.4.14-1
Severity: serious
Tags: d-i
Justification: Breaks debian-installer

I just tested the graphical installer with the new libraries and I'm
afraid there's a serious regression. It looks like old screen content is
not getting "wiped" when new elements get displayed.

As cairo is the only library to have changed recently, I'm fairly
certain that the cause is there, possibly related to the breaking out of
libpixman. I've uploaded some screenshots to show the issue.

Initial screen after boot (no problems):
- http://people.debian.org/~fjp/tmp/d-i/cairo-regression1.png

After scrolling up in the list previously selected lines should not be red:
- http://people.debian.org/~fjp/tmp/d-i/cairo-regression2.png

After scrilling down to English again, the red partly disappears, except
for the two thin lines around Dutch and a line in the left margin:
- http://people.debian.org/~fjp/tmp/d-i/cairo-regression3.png

The next screen still shows text from the previous one ("Choose a
language:" and the "dot" under the s in "Based":
- http://people.debian.org/~fjp/tmp/d-i/cairo-regression4.png

This is the clearest example. It should only be showing a progress bar,
but instead still has the full previous dialog and all progress info is
printed on top of itself, resulting in the almost black bar:
- http://people.debian.org/~fjp/tmp/d-i/cairo-regression5.png

Note that the installer used a directfb backend, not X.

Cheers,
FJP

-- System Information:
Debian Release: lenny/sid
  APT prefers unstable
  APT policy: (500, 'unstable')
Architecture: amd64 (x86_64)

Kernel: Linux 2.6.25 (SMP w/2 CPU cores)
Locale: LANG=en_US.UTF-8, LC_CTYPE=en_US.UTF-8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/bash