Merge "Add split screen API to start two split apps with intents" into tm-qpr-dev am: e8a3e0a57c

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/19379171

Change-Id: I526ba3288b912916937513956c4ee7223c6774dd
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>