Add OnControllableInsetsChangedListener

It's useful for apps to know which inset types they can currently
control, as otherwise they have to poll by calling
controlInsetsAnimation repeatedly.

This can be used when apps want to apply a custom animation
immediately during startup as soon as possible.

Fixes: 150780468
Test: InsetsControllerTest
Test: CTS will be added soon
Test: WindowInsetsActivity
Change-Id: Ic0388c11d759843d3ac9edd8ef23904c9ce05c46