Update PiP on display change

Dispatch OnDisplayChangingListeners upon
any display change in requestStartTransition().

Make sure any display changes with PiP present
also update the PiP bounds and cache relevant information
for future interactions (e.g. boundary conditions).

Bug: 359336365
Flag: com.android.wm.shell.enable_pip2_implementation
Test: fold/unfold while in PiP
Change-Id: I8970576cae758272687c56eb5c43065752006329