Fix toneMapping reference

[greggman]

AFAICT, the spec requires toneMapping period. Even if the browser doesn't support toneMapping.mode = 'extended' it requires it still requires it to exist. It will just be set to 'standard' if the implementation does not support 'extended'.

The only other case is when the canvas has not been configured in which case getConfiguration returns undefined.

Both getConfiguration and toneMapping were added to the spec close enough that any implemetation that supports getConfiguration should be requried to include toneMapping.

[beaufortfrancois]

You're right. See #451 (comment)

[beaufortfrancois]

@kainino0x I believe we can merge this PR. What do you think?

[beaufortfrancois]

I'd like to merge it.

[kainino0x]

Sorry I forgot about this PR because I replied to the spec issue and PR instead.
According to the (open) spec PR the ? is still needed because toneMapping is the thing that won't exist in a browser that doesn't support HDR WebGPU (assuming Safari and Firefox pass through that point before supporting it).
https://github.com/gpuweb/gpuweb/pull/4922/files

[greggman]

According to the (open) spec PR the ? is still needed because toneMapping is the thing that won't exist in a browser that doesn't support HDR WebGPU (assuming Safari and Firefox pass through that point before supporting it).

Can we just require toneMapping? Maybe it's minor but one path is "forgot or didn't know I needed the ? and my app crashes with TypeError: Cannot read properties of undefined" and the other just returns undefined so code checking getConfigure().toneMapping.mode at least doesn't crash.

getConfigure() hasn't shipped to stable so we still have time

[kainino0x]

Require toneMapping and have toneMapping.mode be the thing that's missing on browsers that don't implement it? Would be fine with me.

[beaufortfrancois]

getConfigure() hasn't shipped to stable so we still have time

FYI Chrome always returns toneMapping in getConfiguration() if configuration is not null. See https://source.chromium.org/chromium/chromium/src/+/main:third_party/blink/renderer/modules/webgpu/gpu_canvas_context.cc;l=622;drc=a7b08979892095de2548e193c95e93a01ed8b214