Mismatched parameters in DerivedProperty

[samreid]

During code review #103, we observed In FieldMeasurementTool:

    // This needs to be a new Vector2 instance, so do not pass an output vector to magnet.getFieldVector.
    this.fieldVectorProperty = new DerivedProperty(
      [ this.positionProperty, magnet.positionProperty, magnet.rotationProperty, magnet.strengthProperty ],
      ( position, rotation, strength ) => magnet.getFieldVector( position ), {

Note that the 2nd dependency in the array is position, but the 2nd parameter in the callback is rotation.

[pixelzoom]

Fixed in 839fdd5. Closing.