The RecycleBin facilitates reuse of views across layouts. The RecycleBin has two levels of
storage: ActiveViews and ScrapViews. ActiveViews are those views which were onscreen at the
start of a layout. By construction, they are displaying current information. At the end of
layout, all views in ActiveViews are demoted to ScrapViews. ScrapViews are old views that
could potentially be used by the adapter to avoid allocating views unnecessarily.
This class was taken from Android's implementation of AbsListView which
is copyrighted 2006 The Android Open Source Project.