title: FirebaseApp with name [DEFAULT] doesn't exist
body: <p>After migrating to Firebase Cloud Messaging.When opening my app it crashes and throws an error saying <code>java.lang.IllegalStateException: FirebaseApp with name [DEFAULT] doesn't exist.</code> I already put my new google-services.json and update my SDK. </p>
  
  <p>Here's my MainActivity</p>
  
  <pre><code>public class MainActivity extends Activity {
  
  @Override
  protected void onCreate(Bundle savedInstanceState) {
      super.onCreate(savedInstanceState);
      setContentView(R.layout.activity_main);
  
  //Check Google play service
      GoogleApiAvailability googleAPI = GoogleApiAvailability.getInstance();
      int resultCode = googleAPI.isGooglePlayServicesAvailable(this);
  
      if (resultCode != ConnectionResult.SUCCESS) {
          if (GooglePlayServicesUtil.isUserRecoverableError(resultCode)) {
              GooglePlayServicesUtil.getErrorDialog(resultCode, this,
                      PLAY_SERVICES_RESOLUTION_REQUEST).show();
          } else {
              Log.e(LOG_TAG, "This device is not supported.");
              finish();
          }
      }
  
      Log.i(TAG, "InstanceID token: " + FirebaseInstanceId.getInstance().getToken());
  
  }
  }
  </code></pre>