Map over display function instead of displayed value.

[frasermince]

Previously we were mapping over the displayed status boolean and
treating it like a promise when it wasn't one. I assume we meant to
instead call the display function. I discovered this because I saw on mobile the relocated event wasn't being called when navigating to a chapter that had not yet been loaded. This fixes that issues and makes the relocated event always be called on chapter change.

[fchasen]

Thanks for find this!

Still looking into the promise as something funky is, as you mentioned displayed is just a boolean and it seems to be looking from the promise result of display()

epub.js/src/managers/views/iframe.js

Line 499 in 0127e9e

return displayed.promise;

I don't think we wan't to be calling display here though, since that will trigger a render and this is just looking to know when all the views have finished displaying.

Looking at this, I think a solution could be to add a manager.displayed = [<Promise>] that keeps the results of

epub.js/src/managers/continuous/index.js

Line 122 in 0127e9e

return view.display(this.request);

[fchasen]

On testing some more, my suggestion didn't work at all... will need to tidy this up a bit eventually, but this change works well for now!