>> Speaking of which, if I put an ImageView onto the Scene, and then give
>> it an image, it doesn't auto-size to the image bounds. As a
>> consequence, there isn't a good way of resizing the ImageView to the
>> size of the image.

To resize an ImageView to its default native size you can set
its fitWidth and fitHeight to 0 in the inspector.

We should probably add ImageView to the list of nodes that
support "Use Computed Size" - with a special implementation that
would set the fit size to (0,0).