Stability and logic fixes to PhysicsAnimationLayout to address bugs that leave...

Stability and logic fixes to PhysicsAnimationLayout to address bugs that leave Bubbles in a bad state.

- Ignore attempts to start animations from controllers that aren't the active controller.
- Use -Float.MAX_VALUE for the start velocity default, not 0, so negative velocities aren't discarded.
- Update the SpringForce's final position directly rather than using animateToFinalPosition (the latter is susceptible to race conditions if animateToFinalPosition is called again before the next animation frame, a bug in DynamicAnimation).

Test: atest SystemUITests
Fixes: 131625234
Change-Id: Ie48da88db6c241896bba17bb800a2f91ab61651e