GPUDeviceDescriptor constructor
requiredFeatures are names from GpuFeature; asking for one the adapter
does not have rejects the promise rather than answering a device without
it. requiredLimits is a plain object of name to number — see
gpuRequiredLimits, which builds one.
Implementation
external factory GPUDeviceDescriptor({
String label,
JSArray<JSString> requiredFeatures,
JSObject requiredLimits,
});