* For #11660:added prefetch for topsites
TopSites will be prefetched with observerOnce (wrapper around observerForever).
Also, the SessionControlView.update() is called right away instead of waiting from consumeFrom
in the HomeFragment.onCreateView() which will allow the UI to render all at once on its first
perform traversal
* Removed the submitList(null) since it retriggered a drawing on lower end device
They were both in their packages by themselves, which feels unnecessary.
Unfortunately, a utils pkg is discouraged by kotlin but we don't have a
better place for them right now. Maybe an annotations/ pkg for the
latter?