Better activation experience:
- Hold off on switching out targets until current animation has finished.
- Hide unselected targets when a target is selected.
Code simplification:
- Use explicit callback objects to handle animation updates instead of having MWV implement the interface.
- More compact chevron-loading code.
- Don't use animations for properties that need to change immediately.
Other minor timing tweaks.
Change-Id: I328533e8ab7b4c69c7ba51c8c55002765dcbbd46
1c8d207201