Refactor PiP logic in preparation for expanded state.

- #1: Move logic for handling IME size changes into SysUI, and only rely
      on PinnedStackController to provide bounds when first entering
      PiP and on rotation
- #2: Doing #1 allows us to move PipMotionHelper to SysUI completely, which
      lets us aggregate the animation calls out of PipTouchHandler
- #3: Add proper callbacks to the listeners when the movement bounds
      changed from config change, ime change, or aspect ratio change. This
      allows SysUI to calculate the associated movement bounds for the
      expanded state, and we can then remove the corresponding WM call.
      It also means that SysUI is the only thing that needs to know about
      the expanded state.
- #4: Fix issue where TV was getting the default bounds, not taking the
      aspect ratio when the PiP was entered into account.  Doing #3
      allows us to report the right bounds.
- #5: Remove dead code related to edge snapping/minimizing now that they
      are on by default and associated tuner setting, and controller
      callbacks

Test: android.server.cts.ActivityManagerPinnedStackTests (all existing tests pass)

Change-Id: I3ef361bdf8d44094b4c0a11c70ba4db7d697fdec
Signed-off-by: Winson Chung <winsonc@google.com>