Merge "Add py.typed file to export types to dependents." am: 4e13a43693

Original change: https://android-review.googlesource.com/c/platform/development/+/2363011

Change-Id: Ia6abc4852d51e395fd61a2db43f3439ea5d67b95
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>