Be consistent about where ToComputedValue implementations live.

[emilio]

Right now:

$ cd components/style/values/specified
$ git grep 'impl ToComputedValue' | wc -l
33
$ ../computed
$ git grep 'impl ToComputedValue' | wc -l
14

So that's... not very consistent.

[emilio]

We should decide whether they should live in computed or specified. I don't have a particularly strong preference, and the only argument I've heard (from @mauricioc and @nox IIRC) is that ideally specified modules shouldn't depend on computed ones, and making complex cases depend on that makes the code intrincate.

I think that's a valid point, so lacking other arguments I'd be fine moving all them to computed. But I bet there can be other arguments in the other direction, so given this isn't particularly urgent we can wait and discuss for as long as needed :)

[CYBAI]

IMO, I'll vote for impl ToComputedValue inside specified modules because I think it's reasonable to make associated types of impl ToComputedValue with its computed module.
We can see that we'd like to implement ToComputedValue trait and make its associated type with its own computed module.

I'm also fine for moving all of them in specified modules but just share my opinion.

[nox]

IIRC, I prefer to put them in specified, but I don't remember it well and I'm still on holidays. We can discuss about that next Monday.