src/vs/workbench/api/browser/mainThreadWebviewPanels.ts/MainThreadWebviewPanels/$unregisterSerializer
class MainThreadWebviewPanels:	public $unregisterSerializer(viewType: string): void {
		if (!this._revivers.has(viewType)) {
			throw new Error(`No reviver for ${viewType} registered`);
		}

		this._revivers.deleteAndDispose(viewType);
	}