Merge "[RESTRICT AUTOMERGE] Make MultiClient IMMS PendingIntent IMMUTABLE" into sc-v2-dev am: 59f1ee6a36

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/16170294

Change-Id: Ida87572c8e7f90e84528d066e97c47f802c84da9