Merge "Revert "Revert "Remove IME surface when occured in multi-window mode""" into rvc-dev am: 8ec4d3a33f am: b589824526 am: 7385b9a282

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/11862408

Change-Id: Ibb9e25c0e35ce3fe92538be7c8d7cc5fbac2e90d