Parse const unsafe trait properly

[fee1-dead]

Previously, this was greedily stolen by the fn parsing logic.

r? project-const-traits

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r? @madsmtm

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[fmease]

r? fmease

[fmease]

cc #146122

[fee1-dead]

I quite agree with your comment at #146122 (comment)

[fmease]

Thanks! This is good enough for now. I'm already experimenting with more robust qualifier parsing in a separate project of mine.

Once stage0 rustfmt is bumped we can finally migrate away from the remaining #[const_trait]s in library/ that were left because of this bug.

@bors r+ rollup

[bors]

📌 Commit b145213 has been approved by fmease

It is now in the queue for this repository.