Remove from* variants, move fromString to stringTo (#233)

* Remove from* variants, move fromString to stringTo

* Bump

packages/keyring/src/pair/encode.ts

@@ -2,9 +2,9 @@
 // This software may be modified and distributed under the terms
 // of the ISC license. See the LICENSE file for details.
 
+import stringToU8a from '@polkadot/util/string/toU8a';
 import u8aConcat from '@polkadot/util/u8a/concat';
 import u8aFixLength from '@polkadot/util/u8a/fixLength';
-import u8aFromString from '@polkadot/util/u8a/fromString';
 import naclEncrypt from '@polkadot/util-crypto/nacl/encrypt';
 
 import { PKCS8_DIVIDER, PKCS8_HEADER } from './defaults';
@@ -21,7 +21,7 @@ export default function encode (secretKey: Uint8Array, passphrase?: string): Uin
     return encoded;
   }
 
-  const { encrypted, nonce } = naclEncrypt(encoded, u8aFixLength(u8aFromString(passphrase), 256, true));
+  const { encrypted, nonce } = naclEncrypt(encoded, u8aFixLength(stringToU8a(passphrase), 256, true));
 
   return u8aConcat(nonce, encrypted);
 }