[automerger skipped] Forward fix for: Set FLAG_IMMUTABLE flag on FirstScreenBroadcast PendingIntent. am: 89299047d7 am: 4401663f4a am: 209035afce -s ours am: d11638739c -s ours

am skip reason: Merged-In I70acd4ce48853be728be1fb80b4b885d00a059a9 with SHA-1 5af0edefdb is already in history

Original change: https://googleplex-android-review.googlesource.com/c/platform/packages/apps/Launcher3/+/14936503

Change-Id: I2db3d09a547d2633a4242f479c555c5df93a9e0e