Need to regenerate checks files to match the format used by test-generator

[dstoc]

[dstoc]

Example: https://github.com/dstockwell/web-animations-js/commit/4ccd3f239a651b0c947802b3575636408f7cf816

[dstoc]

While we're doing this we should fix the style.

at(0, function() {
  assert_styles(".anim",{'width':'50px'});
});
at(0.5, function() {
  assert_styles(".anim", [
    {'width':'81.25px'},
    {'width':'81.25px'},
    {'width':'137.5px'},
    {'width':'81.25px'},
    {'width':'95.3125px'},
    {'width':'95.3125px'},
    {'width':'95.3125px'},
  ]);
});

Should be:

at(0, function() {
  assert_styles('.anim', {width: '50px'});
});
at(0.5, function() {
  assert_styles('.anim', [
    {width: '81.25px'},
    {width: '81.25px'},
    {width: '137.5px'},
    {width: '81.25px'},
    {width: '95.3125px'},
    {width: '95.3125px'},
    {width: '95.3125px'},
  ]);
});