[automerger skipped] Merge "[wm] Use existing parent window token for child...

[automerger skipped] Merge "[wm] Use existing parent window token for child windows" into rvc-qpr-dev am: e966c476 am: ec8fa084 -s ours

am skip reason: Change-Id I3efa14fda7a5674a178b13ff6310a526e75e3b50 with SHA-1 347196a3 is in history

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/12629525

Change-Id: I9f47a841a82e3571caf3f2fcf863c220beeffeab