https://webgpu.github.io/webgpu-samples/?sample=worker does not open on any browser

[mwyrzykowski]

Repro:

(1) Open https://webgpu.github.io/webgpu-samples/?sample=worker
(2) Note error (Error in Chrome stable): util.ts:3 Uncaught ReferenceError: window is not defined

I believe this is from a1bafc9 - cc @kainino0x

[kainino0x]

It sure is. I thought that utils file was only used on the main thread since it shows a dialog. Will fix.