Migrate fee payment from Currency to fungible (#2292)

Part of https://github.com/paritytech/polkadot-sdk/issues/226 
Related https://github.com/paritytech/polkadot-sdk/issues/1833

- Deprecate `CurrencyAdapter` and introduce `FungibleAdapter`
- Deprecate `ToStakingPot` and replace usage with `ResolveTo`
- Required creating a new `StakingPotAccountId` struct that implements
`TypedGet` for the staking pot account ID
- Update parachain common utils `DealWithFees`, `ToAuthor` and
`AssetsToBlockAuthor` implementations to use `fungible`
- Update runtime XCM Weight Traders to use `ResolveTo` instead of
`ToStakingPot`
- Update runtime Transaction Payment pallets to use `FungibleAdapter`
instead of `CurrencyAdapter`
- [x] Blocked by https://github.com/paritytech/polkadot-sdk/pull/1296,
needs the `Unbalanced::decrease_balance` fix

substrate/frame/transaction-payment/asset-conversion-tx-payment/src/mock.rs

@@ -24,6 +24,7 @@ use frame_support::{
 	pallet_prelude::*,
 	parameter_types,
 	traits::{
+		fungible,
 		tokens::{
 			fungible::{NativeFromLeft, NativeOrWithId, UnionOf},
 			imbalance::ResolveAssetTo,
@@ -36,7 +37,7 @@ use frame_support::{
 use frame_system as system;
 use frame_system::{EnsureRoot, EnsureSignedBy};
 use pallet_asset_conversion::{Ascending, Chain, WithFirstAsset};
-use pallet_transaction_payment::CurrencyAdapter;
+use pallet_transaction_payment::FungibleAdapter;
 use sp_core::H256;
 use sp_runtime::{
 	traits::{AccountIdConversion, BlakeTwo256, IdentityLookup, SaturatedConversion},
@@ -155,9 +156,13 @@ parameter_types! {
 }
 
 pub struct DealWithFees;
-impl OnUnbalanced<pallet_balances::NegativeImbalance<Runtime>> for DealWithFees {
+impl OnUnbalanced<fungible::Credit<<Runtime as frame_system::Config>::AccountId, Balances>>
+	for DealWithFees
+{
 	fn on_unbalanceds<B>(
-		mut fees_then_tips: impl Iterator<Item = pallet_balances::NegativeImbalance<Runtime>>,
+		mut fees_then_tips: impl Iterator<
+			Item = fungible::Credit<<Runtime as frame_system::Config>::AccountId, Balances>,
+		>,
 	) {
 		if let Some(fees) = fees_then_tips.next() {
 			FeeUnbalancedAmount::mutate(|a| *a += fees.peek());
@@ -171,7 +176,7 @@ impl OnUnbalanced<pallet_balances::NegativeImbalance<Runtime>> for DealWithFees
 #[derive_impl(pallet_transaction_payment::config_preludes::TestDefaultConfig)]
 impl pallet_transaction_payment::Config for Runtime {
 	type RuntimeEvent = RuntimeEvent;
-	type OnChargeTransaction = CurrencyAdapter<Balances, DealWithFees>;
+	type OnChargeTransaction = FungibleAdapter<Balances, DealWithFees>;
 	type WeightToFee = WeightToFee;
 	type LengthToFee = TransactionByteFee;
 	type FeeMultiplierUpdate = ();