Fixed ANR in PinStorage

import java.util.Arrays;

import java.util.Calendar;

import java.util.Date;

import java.util.concurrent.Executors;

import javax.crypto.Cipher;

import javax.crypto.KeyGenerator;

    private final int mBootCount;

    private final KeyStore mKeyStore;

    @Nullable

    private SecretKey mLongTermSecretKey;

    private SecretKey mShortTermSecretKey;

        // The short term key is retrieved later when needed.

        String alias = (!mIsDeviceSecure || mIsDeviceLocked)

                ? KEYSTORE_ALIAS_LONG_TERM_ALWAYS : KEYSTORE_ALIAS_LONG_TERM_USER_AUTH;

        mLongTermSecretKey = initializeSecretKey(alias, /*createIfAbsent=*/ true);

        // This is the main thread, so accessing keystore in a separate thread to prevent ANR.

        Executors.newSingleThreadExecutor().execute(() -> mLongTermSecretKey = initializeSecretKey(

                alias, /*createIfAbsent=*/ true));

        // If the device is not securee or is unlocked, we can start logic. Otherwise we need to

        // wait for the device to be unlocked and store any temporary PIN in RAM.

     * @return true if the operation was successful, false otherwise

     */

    private boolean savePinInformation(SharedPreferences.Editor editor, int slotId,

            StoredPin storedPin, String baseKey, SecretKey secretKey) {

            StoredPin storedPin, String baseKey, @Nullable SecretKey secretKey) {

        if (secretKey == null) {

            // Secret key for encryption is missing

            return false;

    }

    /** Returns the encrypted version of {@code input}, or an empty array in case of error. */

    private byte[] encrypt(SecretKey secretKey, byte[] input) {

    private byte[] encrypt(@Nullable SecretKey secretKey, byte[] input) {

        if (secretKey == null) {

            loge("Encrypt: Secret key is null");

            return new byte[0];