code: public TextMetrics measureWithIdentityTransform(final Context2D context)
      {
          context.save();
  
          context.setToIdentityTransform();
  
          final TextMetrics size = measure(context);
  
          context.restore();
  
          return size;
      }
docs: Returns TextMetrics, which includes an approximate value for
  height. As close as we can estimate it at this time.
  
  @param context
  @return TextMetric or null if the text is empty or null