message: Submit empty string username when on phone number login
diff: @@ -71,7 +71,7 @@ class PasswordLogin extends React.Component {
  ev.preventDefault();
  if (this.state.loginType === PasswordLogin.LOGIN_FIELD_PHONE) {
  this.props.onSubmit(
  - this.state.username,
  + '',
  this.state.phoneCountry,
  this.state.phoneNumber,
  this.state.password,
  