Merge "Postpone window_state_changed events until the window is added" into...

Merge "Postpone window_state_changed events until the window is added" into tm-dev am: 857459ff am: 4db5aded am: 7b5e81f2

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/17741153



Change-Id: I1f86fed063eacd93041934df63e308f57654cb55
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>