While re-doing the image bases for
https://bugs.webkit.org/show_bug.cgi?id=21821, we noticed that this pixel
tests is currently failing:
The behavior differs on Tiger (white square behind the apple absent) and Leopard (white square behind the apple present).
Ignore the above comment. The real issue is that both on Tiger and Leopard, this test is fundamentally not reliable: depending on which tests run before you will get a full gray image or a white square.
See also: bug 101773.