Check whether a user's hashed password needs to be replaced with a new hash.
This is typically called during the login process when the plain text password is available. A new hash is needed when the desired iteration count has changed by a modification of the password-service in the dependency injection container or if the user's password hash was generated in an update like user_update_7000() (see the Drupal 7 documentation).
Alternative implementations of this function might use other criteria based on the fields in $account.
Drupal\user\User: A user object with at least the fields from the {users} table.
boolean TRUE or FALSE.
public function userNeedsNewHash($account);