Refine ViewTreeObserverWrapper

- Make removeOnComputeInsetsListener static.
- Make removeOnComputeInsetsListener only require the listener
  parameter.
- Remove the listener from internal maps while it is removed from the
  observer.

Bug: 169054709
Test: Presubmit
Change-Id: I9807fb8f37565d29ab4ddcc18bf124831cc0aef4