src/vs/workbench/api/browser/mainThreadUrls.ts/MainThreadUrls/$unregisterUriHandler
class MainThreadUrls:	$unregisterUriHandler(handle: number): Promise<void> {
		const tuple = this.handlers.get(handle);

		if (!tuple) {
			return Promise.resolve(undefined);
		}

		const { extensionId, disposable } = tuple;

		this.extensionUrlHandler.unregisterExtensionHandler(extensionId);
		this.handlers.delete(handle);
		disposable.dispose();

		return Promise.resolve(undefined);
	}