that's within current documentation (see "Adobe recommends ..."):
I think you could use BorderContainer as it supports e.g. inline drawing, like:
<s:BorderContainer width="100%" height="100%" id="canvas">
but what should be used as replacement depends I think.
The Canvas component is mostly not necessary, at this point. You can use BorderContainer, as Peter Blazejewicz suggests, but you can also use spark drawing primitives (Rect, Ellipse, Line, etc.) inside any old spark.components.Group. Last, but not least, you can use a Spark Graphic container. I usually use Group, myself.