Fix IME not shown from recents to split-screen task

This reland Id7ac6de6 and make sure to cancel the running animation when
DisplayImeController no longer controlling IME.

Fix: 258814082
Fix: 251906905
Bug: 260534444
Test: repro steps of bugs
Test: atest DisplayImeControllerTest
Test: atest PlatformScenarioTests:BubblesHomeGestureTest
Change-Id: Ibf6055769fc114cdf23e6ecb5895f3a67b714350