-Znext-solver Eager normalization outside of solver

[adwinwhite]

This PR adds a normalization routine for the next solver that behaves the same as the normalization in the old solver.
And it's used to normalize eagerly outside of the next solver.

This is part 2 of modifying the next solver to support eager normalization.

Those test changes are all wording changes, duplicating some errors or reducing some duplicates. But I could have overlooked something.
Notably it fixes the first example of rust-lang/trait-system-refactor-initiative#191, but not the remaining cases.

It's probably easier to review commit by commit.

WIP: maybe remove old deeply_normalize

r? @ghost

[matthiaskrgr]

does this fix #151308 ?

[adwinwhite]

does this fix #151308 ?

Yes, it probably fixes a bunch of issues. And unfix some issues fixed by the next solver? Unsure about that.
Seems tedious to re-triage those labelled fixed-by-the-next-solver 🤔

[adwinwhite]

@bors try @rust-timer queue

[rust-bors]

☀️ Try build successful (CI)
Build commit: 59cc905 (59cc90511d0283377de9ba5a516f11853e3c95a9, parent: 7e0430fafc66bd0fdfaff94e65148a1f207438cd)

[rust-timer]

Finished benchmarking commit (59cc905): comparison URL.

Overall result: ❌✅ regressions and improvements - please read:

Benchmarking means the PR may be perf-sensitive. It's automatically marked not fit for rolling up. Overriding is possible but disadvised: it risks changing compiler perf.

Next, please: If you can, justify the regressions found in this try perf run in writing along with @rustbot label: +perf-regression-triaged. If not, fix the regressions and do another perf run. Neutral or positive results will clear the label automatically.

@bors rollup=never
@rustbot label: -S-waiting-on-perf +perf-regression

Instruction count

Our most reliable metric. Used to determine the overall result above. However, even this metric can be noisy.

	mean	range	count
Regressions ❌ (primary)	-	-	0
Regressions ❌ (secondary)	2.2%	[0.5%, 7.3%]	12
Improvements ✅ (primary)	-0.3%	[-0.3%, -0.3%]	2
Improvements ✅ (secondary)	-2.4%	[-5.0%, -0.2%]	3
All ❌✅ (primary)	-0.3%	[-0.3%, -0.3%]	2

Max RSS (memory usage)

Results (primary -2.5%, secondary -1.6%)

A less reliable metric. May be of interest, but not used to determine the overall result above.

	mean	range	count
Regressions ❌ (primary)	-	-	0
Regressions ❌ (secondary)	-	-	0
Improvements ✅ (primary)	-2.5%	[-2.8%, -2.2%]	2
Improvements ✅ (secondary)	-1.6%	[-2.2%, -1.1%]	2
All ❌✅ (primary)	-2.5%	[-2.8%, -2.2%]	2

Cycles

Results (secondary 3.9%)

A less reliable metric. May be of interest, but not used to determine the overall result above.

	mean	range	count
Regressions ❌ (primary)	-	-	0
Regressions ❌ (secondary)	3.9%	[3.4%, 4.3%]	2
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	-	-	0

Binary size

This perf run didn't have relevant results for this metric.

Bootstrap: 491.487s -> 483.564s (-1.61%)
Artifact size: 394.23 MiB -> 393.40 MiB (-0.21%)