Operating system: elementary 0.4.1
Graphics card: GTX 1080
Broken: 2.80, 6f9819e5fd56
Worked: 2.80, 69b2f5268114
Short description of error
Camera Background Images are not visible in Wireframe mode nor in Cycles Rendered display mode, when the Depth option is set to Back. When the Depth option of background images is set to Front it works in both cases.
It it did work in Wireframe mode in February in 69b2f5268114, but not in Rendered view.
Exact steps for others to reproduce the error
Here's a file demonstratin the issue.
There is no background image visible, unless you set Depth option to Front.