Some tiny modifications. (#8163)

1. fix some typo in the comment.
2. sort the order of methods in 'impl state::Backend for StateDB`

ethcore/src/state/account.rs

@@ -62,7 +62,7 @@ pub struct Account {
 	storage_changes: HashMap<H256, H256>,
 	// Code hash of the account.
 	code_hash: H256,
-	// Size of the accoun code.
+	// Size of the account code.
 	code_size: Option<usize>,
 	// Code cache of the account.
 	code_cache: Arc<Bytes>,
@@ -186,7 +186,7 @@ impl Account {
 	}
 
 	/// Get (and cache) the contents of the trie's storage at `key`.
-	/// Takes modifed storage into account.
+	/// Takes modified storage into account.
 	pub fn storage_at(&self, db: &HashDB, key: &H256) -> trie::Result<H256> {
 		if let Some(value) = self.cached_storage_at(key) {
 			return Ok(value);

ethcore/src/state/mod.rs

@@ -365,7 +365,7 @@ impl<B: Backend> State<B> {
 	pub fn new(mut db: B, account_start_nonce: U256, factories: Factories) -> State<B> {
 		let mut root = H256::new();
 		{
-			// init trie and reset root too null
+			// init trie and reset root to null
 			let _ = factories.trie.create(db.as_hashdb_mut(), &mut root);
 		}
 
@@ -553,8 +553,8 @@ impl<B: Backend> State<B> {
 		// 2. If there's an entry for the account in the global cache check for the key or load it into that account.
 		// 3. If account is missing in the global cache load it into the local cache and cache the key there.
 
-		// check local cache first without updating
 		{
+			// check local cache first without updating
 			let local_cache = self.cache.borrow_mut();
 			let mut local_account = None;
 			if let Some(maybe_acc) = local_cache.get(address) {

ethcore/src/state_db.rs

@@ -440,12 +440,6 @@ impl state::Backend for StateDB {
 		cache.accounts.get_mut(addr).map(|a| a.as_ref().map(|a| a.clone_basic()))
 	}
 
-	fn get_cached_code(&self, hash: &H256) -> Option<Arc<Vec<u8>>> {
-		let mut cache = self.code_cache.lock();
-
-		cache.get_mut(hash).map(|code| code.clone())
-	}
-
 	fn get_cached<F, U>(&self, a: &Address, f: F) -> Option<U>
 		where F: FnOnce(Option<&mut Account>) -> U {
 		let mut cache = self.account_cache.lock();
@@ -455,6 +449,12 @@ impl state::Backend for StateDB {
 		cache.accounts.get_mut(a).map(|c| f(c.as_mut()))
 	}
 
+	fn get_cached_code(&self, hash: &H256) -> Option<Arc<Vec<u8>>> {
+		let mut cache = self.code_cache.lock();
+
+		cache.get_mut(hash).map(|code| code.clone())
+	}
+
 	fn note_non_null_account(&self, address: &Address) {
 		trace!(target: "account_bloom", "Note account bloom: {:?}", address);
 		let mut bloom = self.account_bloom.lock();