Apply Recovery::Forbidden when reparsing pasted macro fragments.

[nnethercote]

Fixes #137874.

The changes to the output of tests/ui/associated-consts/issue-93835.rs
partly undo the changes seen when NtTy was removed in #133436, which
is good.

r? @petrochenkov

[nnethercote]

This is the exact spot where the problem was occurring:

rust/compiler/rustc_parse/src/parser/pat.rs

Lines 794 to 804 in 00095b3

	// Don't eagerly error on semantically invalid tokens when matching
	// declarative macros, as the input to those doesn't have to be
	// semantically valid. For attribute/derive proc macros this is not the
	// case, so doing the recovery for them is fine.
	else if self.can_be_ident_pat()
	|| (self.is_lit_bad_ident().is_some() && self.may_recover())
	{
	// Parse `ident @ pat`
	// This can give false positives and parse nullary enums,
	// they are dealt with later in resolve.
	self.parse_pat_ident(BindingMode::NONE, syntax_loc)?

The self.may_recover() was false on the original parse and then true on the reparse.

[rustbot]

This PR changes a file inside tests/crashes. If a crash was fixed, please move into the corresponding ui subdir and add 'Fixes #' to the PR description to autoclose the issue upon merge.

[petrochenkov]

@bors r+

[bors]

📌 Commit b9e13cb has been approved by petrochenkov

It is now in the queue for this repository.