Merge typeck loop with static/const item eval loop
r? `@ghost`
Let's try a small one first. Doing this in general has some bad cache coherence issues because the query caches are laid out in `Vec<QueryResult>` lists per query where each index refers to a `DefId` in the same order as we're iterating. Iterating two or more lists at the same time does have cache issues, so I want to poke a bit at it to see if we can't merge just a few of them at a time.