Remove all instances of fragment_infos and fragment sets

[Nashenas88]

Remove unused fragment structs. This was suggested by @eddyb in IRC: botbot link.

[rust-highfive]

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[Nashenas88]

r? @eddyb

[aidanhs]

Thanks for the PR @Nashenas88! We'll keep an eye on it to make sure @eddyb or another reviewer gets to it soon.

[Nashenas88]

Looking into the failures now.

[Nashenas88]

So it seems the failing tests are just verifying the internal workings of the code that was just deleted (unless I misinterpreted them). Are there already tests for what replaced this (making these also candidates for deletion)? Or should these be modified to verify the functionality of the code that replaced fragment infos?

[eddyb]

@Nashenas88 Fragments were a dead-end in dynamic drop that never got used in practice.
MIR drop elaboration is more sophisticated and has its own tests etc. You can remove the fragment ones.

[eddyb]

@bors r+

[bors]

📌 Commit a563f35 has been approved by eddyb

[Nashenas88]

@eddyb bump for merge?

[Mark-Simulacrum]

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