Modified current animation logic to use callbacks from the controllers
to further clean and modularize code.
Test: Pixel 3XL device, atest PointerController_test, compile
Change-Id: I1073bd78687cca491663c0349751dab4b30aa8e2
Abstracted logic that applies to all pointer types into general
PointerController class and moved implementation of logic specific
to the mouse cursor and touch spots to MouseCursorController and
TouchSpotController, respectively.
Test: Pixel 3XL device, atest PointerController_test, compile
Change-Id: Ia5825c37ca75951cc8bcd7d5102c986bd957e69f
