Viewer component baseLayer behavior is inconsistent with Cesium

[mfarmer-ara]

On Cesium's Viewer doc, it expects baseLayer to be:

ImageryLayer | false or undefined.

In Resium's Viewer.ts, it is forcing baseLayer to be undefined when it is set to false.

This is causing the map to reach out https://api.cesium.com/v1/assets/2/endpoint to when you want to turn off baseLayerPicker and baseLayer in favor of the ImageryLayer component as Cesium falls back to the Ion behavior if baseLayer is not explicitly false.

[mfarmer-ara]

<Viewer
                id="LocationFromMap"
                ref={refViewer}
                full
                baseLayerPicker={false}
                timeline={false}
                homeButton={false}
                geocoder={false}
                fullscreenButton={false}
                vrButton={false}
                navigationHelpButton
                animation={false}
                selectionIndicator={false}
                baseLayer={false}
            >
           <ImageryLayer
                        imageryProvider={new UrlTemplateImageryProvider({
                           url: `${buildModuleUrl('Assets/Textures/NaturalEarthII')}/{z}/{x}/{reverseY}.jpg`,
                           tilingScheme: new GeographicTilingScheme(),
                           maximumLevel: 2,
                        });}
           />
    </Viewer>

The viewer code above (approximately) gives the following console errors due to baseLayer being forced to be undefined if it's false:

If it's allowed to be false (not undefined) these don't happen. A token may also be appended to the first request if Cesium.Ion.defaultAccessToken is not set to undefined.

[beaumcgee]

Happy to see I'm not the only person experiencing this. I've been chasing this same error for the last couple days while trying to get Resium to work in an offline (aka no internet connection) environment. This issue doesn't prevent any functionality but does pollute the web console with Ion InvalidCredentials errors. This is after carefully following the Resium documentation and Cesium Offline Guide here: Guide.