Don't call with_reveal_all_normalized in const-eval when param_env has inference vars in it

[compiler-errors]

what: This slightly shifts the order of operations from an existing hack:

rust/compiler/rustc_middle/src/ty/consts/kind.rs

Lines 225 to 230 in 5b6ed25

	// HACK(eddyb) when the query key would contain inference variables,
	// attempt using identity substs and `ParamEnv` instead, that will succeed
	// when the expression doesn't depend on any parameters.
	// FIXME(eddyb, skinny121) pass `InferCtxt` into here when it's available, so that
	// we can call `infcx.const_eval_resolve` which handles inference variables.
	let param_env_and = if param_env_and.needs_infer() {

in order to avoid calling a tcx query (TyCtxt::reveal_opaque_types_in_bounds, via ParamEnv::with_reveal_all_normalized) when a param-env has inference variables in it.

why: This allows us to enable fingerprinting of query keys/values outside of incr-comp in deubg mode, to make sure we catch other places where we're passing infer vars and other bad things into query keys. Currently that (bbf3383) crashes because we introduce inference vars into a param-env in the blanket-impl finder in rustdoc 😓

rust/src/librustdoc/clean/blanket_impl.rs

Line 43 in 5b6ed25

let param_env = EarlyBinder(param_env).subst(infcx.tcx, substs);

See the CI failure here: https://github.com/rust-lang/rust/actions/runs/4058194838/jobs/6984834619

[rustbot]

r? @jackh726

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[jackh726]

@bors r+

[bors]

📌 Commit 789e828 has been approved by jackh726

It is now in the queue for this repository.

[bors]

⌛ Testing commit 789e828 with merge f77f4d5...

[bors]

☀️ Test successful - checks-actions
Approved by: jackh726
Pushing f77f4d5 to master...

[rust-timer]

Finished benchmarking commit (f77f4d5): comparison URL.

Overall result: no relevant changes - no action needed

@rustbot label: -perf-regression

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