…nGetter

Because:
1. All references to this function have already been annotated with `__PURE__`;
2. It's not exported.

Therefore, adding `__NO_SIDE_EFFECTS__` does not reduce the bundle size.

Moreover, somehow, when bundling `runtime-dom.global.prod.js`, Rollup does not delete this comment even though it's not exported at all, so it even increases the bundle size a bit.