Use Box<CalcLengthOrPercentage> in specified values to avoid bloating inline sizes
For #15061
CalcLOP is a large struct, and gets used quite often. While #15063 reduces its size a bit,
it will still be much larger than any of the other variants in the `specified::Length*` types,
so it will still bloat sizes, especially for specified values that contain many lengths.
This change boxes it in the length types, so that it just takes one word.
r? @heycam
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Treat top-level number in calc() invalid
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This should probably considered as a temporary fix (for [bug 1321206](https://bugzilla.mozilla.org/show_bug.cgi?id=1321206)), to avoid assertion when trying to serialize calc value with only numbers. Certain properties (e.g. `line-height`) would eventually need to keep numbers inside calc.
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Currently, CalcLengthOrPercentage doesn't actually keep the number value. If we don't treat it invalid, we can end up generating empty `calc()` value when one contains numbers (e.g. `calc(1)`), which would violate assertion elsewhere that `calc` must not be empty.
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Currently, CalcLengthOrPercentage doesn't actually keep the number
value, so if we don't treat it invalid, we can end up generating empty
`calc()` value when one contains top-level numbers (e.g. `calc(1)`),
which would violate assertion elsewhere that `calc` must not be empty.
Only allow border-image-outset to use non-negative numbers.
Restricts border-image-outline to only allow positive values.
Fixes#14295
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This commit itself only moves things around and adds an extra parameter to the
`apply_declarations` function to eventually handle #14079 correctly.
Probably needs a more granular API to query fonts, á la nsFontMetrics, but
that's trivial to do once this is landed.
Then we should make the font provider mandatory, and implement the missing stylo
bits.
