vcl: make all members of ImplAnimView private

I'm making Animation a friend class of ImplAnimView. Nothing should be using
ImplAnimView other than Animation - so to enforce this I'm making all member
functions private. This is part of general cleanup of vcl's Animation.

Change-Id: Ib4746d31c14b1b2caeed61cae99c61fca0e02abc
vcl: rename ImplAnimView functions to more readable names

Change-Id: I47e888bcd08cadcbbd3788b264a478c56af4d063