Clean up unused Account and it's leftovers from the backend (paritytech#547)

* Remove useless acccount

* Remove useless basic conversion

Co-authored-by: dmitrylavrenov <[email protected]>

Author: MOZGIII

frame/evm/src/backend.rs

@@ -28,16 +28,6 @@ use sha3::{Keccak256, Digest};
 use evm::backend::{Backend as BackendT, ApplyBackend, Apply};
 use crate::{AccountStorages, AccountCodes, Config, Event, Pallet};
 
-#[derive(Clone, Eq, PartialEq, Encode, Decode, Default)]
-#[cfg_attr(feature = "std", derive(Debug, Serialize, Deserialize))]
-/// Ethereum account nonce, balance and code. Used by storage.
-pub struct Account {
-	/// Account nonce.
-	pub nonce: U256,
-	/// Account balance.
-	pub balance: U256,
-}
-
 #[derive(Clone, Eq, PartialEq, Encode, Decode)]
 #[cfg_attr(feature = "std", derive(Debug, Serialize, Deserialize))]
 /// Ethereum log. Used for `deposit_event`.
@@ -117,12 +107,7 @@ impl<'vicinity, T: Config> BackendT for Backend<'vicinity, T> {
 	}
 
 	fn basic(&self, address: H160) -> evm::backend::Basic {
-		let account = Pallet::<T>::account_basic(&address);
-
-		evm::backend::Basic {
-			balance: account.balance,
-			nonce: account.nonce,
-		}
+		Pallet::<T>::account_basic(&address)
 	}
 
 	fn code_size(&self, address: H160) -> usize {