[wasm] Use cross origin policy headers

[maraf]

Use xharness arg --web-server-use-cop to set cross origin policy headers

Cross-Origin-Embedder-Policy: require-corp
Cross-Origin-Opener-Policy: same-origin

In Chrome 92 SharedArrayBuffer was disabled due to a vulnerability. To enable it site must be cross-origin isolated (by COEP and COOP headers). More info at https://developer.chrome.com/blog/enabling-shared-array-buffer/.

Fixes#61945

[ghost]

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Issue Details

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Use xharness arg --web-server-use-cop to set cross origin policy headers

Cross-Origin-Embedder-Policy: require-corp
Cross-Origin-Opener-Policy: same-origin

Fixes #61945

Author:	maraf
Assignees:	-
Labels:	arch-wasm, area-System.Runtime.InteropServices.JavaScript
Milestone:	7.0.0

[radical]

@maraf could you add a reasoning for the change? @kg had pointed to https://developer.chrome.com/blog/enabling-shared-array-buffer/ , and that would be useful to add to the PR description too.

[maraf]

There is a misalignment between Xharness and Arcade versions.
This will be solved by #61668.