Description
If I specify binding groups in wgsl (using reflection, no layout), I can specify for instance group 0 and 2 (and skip 1), but when I try to bind that in the application I get an error.

Repro steps
https://github.com/FredrikNoren/wgpu/tree/gap-bug/wgpu/examples/hello-triangle

Expected vs observed behavior
I'm getting the following error in the example: current render pipeline has a layout which is incompatible with a currently set bind group, first differing at entry index 0.

Platform
OSX

(@kvark requested that I filed this issue)