Minor Uniques pallet improvements and XCM v3 preparations

[gavofyork]

Cumulus companion: paritytech/cumulus#1070

Several small additions to make Uniques pallet more useful and provide traits for Polkadot's XCM v3.

Traits

Introduces ContainsPair trait which is basically the same as Contains except the contains function can accept both pair members as references, rather than a reference to a pair which as with the basic Contains trait.

Additional logic combinator structs are introduced which work on both Contains and ContainsPair allowing membership-intersection, exclusion and combinations thereof.

Introduces EnsureOriginWithArg, a trait similar to EnsureOrigin, except that it can take an additional reference argument with which the origin may be validated and from which the Success value may determined.

Uniques Pallet

Removes the Default and HasCompact bounds from both ClassId and InstanceId types.

Also removes the From<u16> bound of ClassId and InstanceId which is needed for benchmarks and replaces with a BenchmarkHelper trait which provides the same facility but without avoiding the need for the bound.

Would be nice to also remove the Copy bound which is also mostly for benchmarks.

NOTE: This changes the transaction format.

set_accept_ownership is introduced as a transaction and there must be prior approval by the new owner with this for a transfer of asset class ownership to succeed.

A new config trait item is introduced CreateOrigin, based around the new trait EnsureOriginWithArg, allowing origins to be vetted and the account ID to be determined taking the class ID into account. This allows for the possibility of allowing only certain origins to be able to create certain NFT classes.

Downstream

Two new trait config items must be added to pallet_uniques::Config impl block. For equivalent behaviour to previous versions, use:

use frame_system::EnsureSigned;
use frame_support::traits::AsEnsureOriginWithArg;
impl pallet_uniques::Config for Runtime {
    // snip
    type Helper = ();
    type CreateOrigin = AsEnsureOriginWithArg<EnsureSigned<AccountId>>;
}

[ox12giant]

This dependency
use frame_support::traits::AsEnsureOriginWithArg; is not available with frame-support = { version = "4.0.0-dev", default-features = false, git = "https://github.com/paritytech/substrate.git", branch = "polkadot-v0.9.17" }

Error

use frame_support::traits::{AsEnsureOriginWithArg, ConstU128, ConstU64, ConstU32, ConstU8, KeyOwnerProofSystem, Randomness, StorageInfo},
     |              ^^^^^^^^^^^^^^^^^^^^^ no `AsEnsureOriginWithArg` in `traits`

[gilescope]

@ox12giant it missed the cut for v0.9.18 by a day or two so it will be in polkadot-v0.9.19 substrate branch (once created).

[ox12giant]

Awesome~!