Merge "Icon: make Icon's Bitmaps immutable" into tm-dev am: 227085759c am: 307dba797c

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/17803565

Change-Id: I423e04c11dfed46f476d41a15546ae5d2e51bdea
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>