Attempt to fix infinite recursion.

When collapsing a panel without animating, it might be that an
overscroll animating was still running, and thus expandedHeight != 0
even if we set expandedFraction manually to 0, which sets the state
to STATE_OPEN again and tries to close it in an infinite loop.

Bug: 15721600
Change-Id: I14e0ee43fb4a47286d618cc97581d4e4a98fb2a2