Amendment to solution for #260: when in `mountAll` mode (initial render of a component), attempt to re-use parent's `base` for high-order children that do not initialize with a recycled `base`.
Amendment to solution for #260: when in `mountAll` mode (initial render of a component), attempt to re-use parent's `base` for high-order children that do not initialize with a recycled `base`.

neeharv/preact,neeharv/preact,developit/preact,developit/preact,gogoyqj/preact