SAM 2's instance now reads wgpu's environment variables, as the render context's does, so a driver such as
Mesa's Dozen (WGPU_ALLOW_UNDERLYING_NONCOMPLIANT_ADAPTER=1) is visible to it, and WGPU_POWER_PREF applies.
An adapter without compute shaders is refused before a device is made on it, so the CPU takes over with one
line instead of a validation error per kernel. The refused adapter is kept for the life of the process, as
the device on it was: dropping it crashed the tests on WSL2's GL driver. Gpu::shared no longer repeats
"SAM 2 compute:" in its errors.
JonRC
50e5a7970e