@Test(expected = AuthFailureError.class)
public void failedGetAuthToken() throws Exception {

    when(mAccountManager.getAuthToken(mAccount, "cooltype", false, null, null))
            .thenReturn(mFuture);
    when(mFuture.getResult()).thenThrow(new AuthenticatorException("sadness!"));
    mAuthenticator.getAuthToken();
}