Test: width:49%; height:auto; width="70" height="20%" viewBox="0 0 1 1"
This testcase checks that the intrinsic ratio will be taken from the
'viewBox' attribute when the CSS 'height' property is set to 'auto', the
'width' property is set to some other value, and the 'width' and 'height'
attributes do not provide an intrinsic ratio. You should see a blue square
with sides 49% the height of the content area when viewing this file.