Upgrade wgpu

[DJMcNab]

Wgpu 0.9 has released, now under MIT/Apache 2.0 🎉

We can't remove MPL-2.0 from the deny.toml, because wgpu_subscriber is still under MPL.

[DJMcNab]

I've also tried to enable validation again, without success

Naga still chokes on our compute shader, with exceedingly unhelpful error messages.

[khyperia]

@VZout I vaguely recall there was a reason you used wgpu-subscriber instead of env_logger in #92, am I misremembering and this change is fine, or is there a reason?

[DJMcNab]

I think wgpu moved to just log in gfx-rs/wgpu#1211 (comment)

[VZout]

Why map during creation and then immediately unmap?

[DJMcNab]

That's required to actually get values from the queries - there's a wgpu issue about it, which I can't find at the moment

[VZout]

🤦

[DJMcNab]

gfx-rs/wgpu#1374 (comment)

[VZout]

@VZout I vaguely recall there was a reason you used wgpu-subscriber instead of env_logger in #92, am I misremembering and this change is fine, or is there a reason?

The reason we used wgpu-subscriber was because back then the triangle example in the wgpu repo used wgpu-subscriber. I'm not aware of any other reason. I think env logger is better anyway. gives you pretty colors. (And I get the feeling subscriber is abandoned?)