If we are interpolating between a dimension and a percentage value and
the dimension component is 0, we now return a percentage value rather
than a `calc()` value.
We also support interpolating from a CalculatedStyleValue to a
compatible dimension or percentage style value.
This also brings with it a couple of improvements in how we handle
interpolation between mixed dimension and percentage types in terms of:
- Proper simplification of the resulting calc()
- Improved handling of interpolation outside the 0-1 range
This changes the maximum number of decimal places from 5 to 6, but 5 was
previously a guess, and not specified behaviour:
> For all of the decimal changes (except color) I couldn't really find a
> spec that mandates any required precision, so I just copied what
> Firefox seems to do, which is limit the output to 5 decimal places.
> https://github.com/SerenityOS/serenity/pull/23449
We now clamp the values returned from calc into the allowed range (where
we know it) and censor any `NaN`s to `0` both when we resolve and when
we serialize.
Gains us 76 WPT passes.
