@Override
  public boolean onOptionsItemSelected(MenuItem item) {
    switch (item.getItemId()) {
      case android.R.id.home:
        this.onBackPressed();
        break;
    }
    return true;
  }
A {@link android.preference.PreferenceActivity} which implements and proxies the necessary calls
to be used with AppCompat. Largely inspired from the AOSP support-v7 demos.
java/com/google/android/apps/authenticator/settings/AppCompatPreferenceActivity.java