rokeStyle = ColorScheme.getColorForReservedNameAsString('black');
      tr.ui.b.drawLine(
          ctx, viewLeft, viewTop, viewLeft, viewBottom, viewLeft);
      ctx.stroke();
      ctx.closePath();

      // Draw y-axis ticks and gridlines.
      ctx.beginPath();
      ctx.strokeStyle = ColorScheme.getColorForReservedNameAsString('grey');

      const majorMarkHeight = this.majorMarkHeightWorld_(transform, pixelRatio);
      const maxMajorMark = Math.max(transform.viewYToWorldY(viewTop),
          Math.ab