Drop Tranche location

[NunoAlexandre]

Currently, the pool_system::tranches::create_metadata function defines the AssetMetadata.location field as follows:

location: Some(VersionedMultiLocation::V3(MultiLocation {
	parents: 1,
	interior: X3(
		Parachain(parachain_id.into()),
		PalletInstance(pallet_index),
		// todo(nuno): revisit this
		GeneralKey {
			length: 16u8,
			data: vec_to_fixed_array(tranche_id),
		},
	),
})),

I remember suggesting this structure many months back, but as I am updating the codebase to Polkadot v0.9.38 and XCM v3 and bumped into this, I realised we don't need a location for tranche tokens at all. Tranche tokens are not to be handled through XCM due to their permissions nature and we are building support for permissioned transfers through Connectors.

Suggestion

Basically set location to None and adjust all tests.

+ location: None,
- location: Some(VersionedMultiLocation::V3(MultiLocation {
- 	parents: 1,
- 	interior: X3(
- 		Parachain(parachain_id.into()),
- 		PalletInstance(pallet_index),
- 		// todo(nuno): revisit this
- 		GeneralKey {
- 			length: 16u8,
- 			data: vec_to_fixed_array(tranche_id),
- 		},
- 	),
- })),

[NunoAlexandre]

@mustermeiszer @offerijns what do you think? Any objections?

[mustermeiszer]

Sounds good and agreed!

[NunoAlexandre]

Great, done in 61f2960. I will also include a migration that sets the location of any existing tranche token in the registry to None.

[mustermeiszer]

I am not the biggest fan of having this in 38. But I also know that having intermediate branches is annoying. But could cherru pick the commit and create a PR. Especially given we need a migration. WDYT?

[NunoAlexandre]

I am not the biggest fan of having this in 38. But I also know that having intermediate branches is annoying. But could cherru pick the commit and create a PR. Especially given we need a migration. WDYT?

You are absolutely right. I am always advocating for smaller, self-contained PRs but this time I went against my own principle. I will backport it to a new PR based of the latest main and add the migration part as well. Thanks for the feedback 🤟