This patch replaces the handwritten MallocSizeOf implementation for
PropertyDeclaration with a derived one, which gives much more thorough
measurement.
This requires (a) deriving MallocSizeOf for a *lot* of additional types (most
of which already have `derive(HeapSizeOf)` in Servo builds), and (b)
implementing MallocSizeOf for a few more types in the `malloc_size_of` crate.
These changes would significantly improve the reporting coverage for gmail if
it weren't for the fact that SpecifiedUrl isn't measured due to a lack of
clarity about its fields; that can be fixed as a follow-up once bug 1397971 has
landed.
Three keyword types are created through a macro but have some of their
impl's handled elsewhere. Since all impl's are the same, this commit
moves them into the macro to have them auto generated, for more concise
code.
Add support for keyword values for min-width and max-width
This is a follow-up to #14432 which got closed and can no longer be re-opened.
This PR aims to add support for keyword-values max-content, min-content, fit-content, and fill-available to the properties that use them, namely min-width, min-height, max-width, and max-height.
It's still untested because I still haven't figured out how to do that. I guess I should write or find some web page that uses these properties.
Refs #13821.
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Implement an ExtremumLength type which contains all the enumerated
keyword values for min-width, min-height, max-width, and
max-height. Then, implement a MinLength which can be used for min-width
and min-height. So far this just maps to Gecko values.
Refs #13821.
