My benchmark which spend most time preparing function parameters
takes `250 ms` now, from `510 ms` before. This is mainly achieved by
doing less unnecessary work and by giving the compiler more inlined
code to optimize.
* Reserve correct vector sizes and use unchecked `append` function.
* Construct `GVArray` parameters directly in the vector, instead of
moving/copying them in the vector afterwards.
* Inline some constructors, because that allows the compiler understand
what is happening, resulting in less code.
This probably has negilible impact on the user experience currently,
because there are other bottlenecks.
Differential Revision: https://developer.blender.org/D15009
This does two things:
* Introduce new `materialize_compressed` methods. Those are used
when the dst array should not have any gaps.
* Add materialize methods in various classes where they were missing
(and therefore caused overhead, because slower fallbacks had to be used).
