[automerger skipped] Add android:exported tag am: 2fe8554eae -s ours am: 6d9b730332 -s ours

am skip reason: Merged-In Icf7492e392cf20986990be2752e6357d4cdb352c with SHA-1 c61b39439e is already in history

Original change: https://googleplex-android-review.googlesource.com/c/platform/developers/samples/android/+/15828964

Change-Id: I6d1577f41d4e0597864ca45205d26e70c1b99789