Merge "Add a mutability flag to the PendingIntent" am: 2a4ac569b0 am: 0cfb318d10 am: 49a146399c

Original change: https://android-review.googlesource.com/c/platform/frameworks/base/+/1456120

Change-Id: I7018d8afbd43690810d6b00683c6e7d26091e8ae