move Account to solana-sdk (#13198)

sdk/src/nonce_account.rs

@@ -0,0 +1,37 @@
+use crate::{
+    account::Account,
+    account_utils::StateMut,
+    fee_calculator::FeeCalculator,
+    hash::Hash,
+    nonce::{state::Versions, State},
+};
+use std::cell::RefCell;
+
+pub fn create_account(lamports: u64) -> RefCell<Account> {
+    RefCell::new(
+        Account::new_data_with_space(
+            lamports,
+            &Versions::new_current(State::Uninitialized),
+            State::size(),
+            &crate::system_program::id(),
+        )
+        .expect("nonce_account"),
+    )
+}
+
+pub fn verify_nonce_account(acc: &Account, hash: &Hash) -> bool {
+    match StateMut::<Versions>::state(acc).map(|v| v.convert_to_current()) {
+        Ok(State::Initialized(ref data)) => *hash == data.blockhash,
+        _ => false,
+    }
+}
+
+pub fn fee_calculator_of(account: &Account) -> Option<FeeCalculator> {
+    let state = StateMut::<Versions>::state(account)
+        .ok()?
+        .convert_to_current();
+    match state {
+        State::Initialized(data) => Some(data.fee_calculator),
+        _ => None,
+    }
+}