Please add support for repeating a pattern in a shape, similar to pattern fill support for the HTML canvas.

https://developer.mozilla.org/en-US/docs/Web/API/CanvasRenderingContext2D/createPattern

What I would like to do is draw a small pattern using the existing lines, rects, circles, and other shapes. I would then like to use this pattern as the fill for drawing other elements on the canvas, instead of just a color.

i.e., currently I can draw a rectangle with a solid fill color like so:

  void drawRect(Rectangle<num> bounds, Color fill) {
    final paint = new Paint();
    paint.color = new Color.fromARGB(fill.a, fill.r, fill.g, fill.b);
    paint.style = PaintingStyle.fill;

    canvas.drawRect(bounds, paint);
  }

Instead, I would like to have something like a PantingStyle.repeat, where I can set another canvas element (or similar construct) as the source for the pattern to repeat.