Background map invisible on globe

[JanisGailis]

Expected behavior

When opening the Cate GUI from a newly installed Cate installation, the Cesium globe should appear.

Actual behavior

The globe is there, but is invisible because of this error in the developer console:

An error occurred in "BingMapsImageryProvider": An error occurred while accessing http://dev.virtualearth.net/REST/v1/Imagery/Metadata/Aerial?incl=ImageryProviders&key=AnCcpOxnAAgq-KyFcczSZYZ_iFvCOmWl0Mx-6QzQ_rzMtpgxZrPZZNxa8_9ZNXci.

Steps to reproduce the problem

I just uninstalled Cate 0.9.dev6 (both core and GUI) and installed Cate 0.9.dev7. When opening it up, I had no Globe. I think I saw this once before with Cate 0.9.dev6 as well.

Specifications

Windows 10, Cate 0.9.dev7 installed with installers

[forman]

Seems that Bing service wasn't available at that time.
I will catch the error and fall back to a static map.