How to create MapImageLayer from MapImage in 4.1

Question

I'm trying to find the equivalent in 4.1 to the 3.x's MapImageLayer.addImage method, e.g.

mapImageLayer.addImage(new MapImage({
    extent : extentForDataUrl,
     href : someDataUrlString
}));

AndyGup · Answer

Update as of July 2017: "Coming soon not to be confused with the 4x MapImageLayer which is the 4x version of the 3x ArcGISDynamicMapServiceLayer)"

Reference: Functionality matrix | ArcGIS API for JavaScript 4.4

JamesWiggins · Answer

Is there any update to this? I am running into the same issue.