Animation test of attributeType
For a blue rectangle width and height is animated,
but for the width animation the attributeType is
set to CSS. Because there is no CSS width property
for rect, this has no visible effect, only the height
is animated, because the attributeType is set to
XML for this animation.
The animation is compared with an underlying
animated red rectangle. The blue rectangle covers
the red one always completely. If something
red gets visible, an error is occured.