borrowck: Simplify deps to build compiler 30s faster

[joshtriplett]

rustc_borrowck uses two helpers from rustc_traits. One of them is re-exported from rustc_trait_selection, and the other can easily move to rustc_trait_selection.

Making rustc_borrowck use these helpers from rustc_trait_selection directly, and eliminating the rustc_traits dependency, allows starting to build rustc_borrowck earlier, which substantially speeds up building the compiler because rustc_borrowck is one of the last things to build.

On my system, this speeds up the rustc build by a little over 30s.

[rustbot]

r? @TaKO8Ki

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[rustbot]

These commits modify the Cargo.lock file. Unintentional changes to Cargo.lock can be introduced when switching branches and rebasing PRs.

If this was unintentional then you should revert the changes before this PR is merged.
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[mejrs]

@bors try @rust-timer queue

[rust-bors]

☀️ Try build successful (CI)
Build commit: f1bf412 (f1bf412ba34726c72fd27fb00f7b35c908c57318)
Base parent: 73dc916 (73dc9167f1cd099e525c9ade2e068d1907b78564)

[rust-timer]

Finished benchmarking commit (f1bf412): comparison URL.

Overall result: no relevant changes - no action needed

Benchmarking means the PR may be perf-sensitive. Consider adding rollup=never if this change is not fit for rolling up.

@rustbot label: -S-waiting-on-perf -perf-regression

Instruction count

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

Max RSS (memory usage)

Results (primary 3.4%, secondary 0.5%)

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

	mean	range	count
Regressions ❌ (primary)	3.4%	[0.5%, 6.4%]	2
Regressions ❌ (secondary)	0.5%	[0.4%, 0.6%]	5
Improvements ✅ (primary)	-	-	0
Improvements ✅ (secondary)	-	-	0
All ❌✅ (primary)	3.4%	[0.5%, 6.4%]	2

Cycles

Results (primary 0.1%, secondary -0.4%)

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

	mean	range	count
Regressions ❌ (primary)	0.7%	[0.5%, 1.1%]	5
Regressions ❌ (secondary)	0.7%	[0.5%, 1.0%]	6
Improvements ✅ (primary)	-0.7%	[-0.9%, -0.6%]	4
Improvements ✅ (secondary)	-2.1%	[-2.9%, -1.0%]	4
All ❌✅ (primary)	0.1%	[-0.9%, 1.1%]	9

Binary size

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

Bootstrap: 490.553s -> 487.967s (-0.53%)
Artifact size: 390.33 MiB -> 390.35 MiB (0.01%)

[joshtriplett]

AIUI, the perf suite bootstrap timing uses -j1, so it isn't picking up on improvements that primarily help builds with higher parallelism. This was a 30s improvement on my system with -j12.