More complete implementation of "lose the device".

[bradwerth]

Checklist

• Run cargo clippy.
• Run cargo clippy --target wasm32-unknown-unknown if applicable.
• Add change to CHANGELOG.md. See simple instructions inside file.

Connections
N/A

Description
This provides a way for wgpu-core to specify a callback on "lose the device". It ensures this callback is called at the appropriate times: either after device.destroy has empty queues, or on demand from device.lose.

Testing
A test has been added to device.rs.

[nical]

Nitpick: "callback" instead of "closure", otherwise 👍

[bradwerth]

Nitpick: "callback" instead of "closure", otherwise 👍

The remaining use of "closure" is in DeviceLostClosure which wraps DeviceLostCallback and DeviceLostCallbackC. I can't rename that to use "callback" without introducing naming redundancy. This naming is also matching the naming pattern established by SubmittedWorkDoneClosure. I'm going to leave this as it is.