[AD] Possible regression with OpenGL

[Peter Wang <novalazy@xxxxxxxxxx>]

Hi,

I just noticed that r15460[1] causes the test_driver to show a number of
black screens when running most of the bitmap tests, e.g. you can see it
with

    ./test_driver -d ../../tests/test_bitmaps.ini

Peter

[1] "Do not preserve bound texture state. (this was discussed before but
only done in the primitives addon). Minor cleanup. Minor fix for Android
Galaxy player and possibly other Androids."