Merge "Revert "Icon: make Icon's Bitmaps immutable"" into tm-dev am: 4e8c47ef am: 1837e9ec am: 288097c3 am: d6e5195d

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/17919920



Change-Id: Ic4051217bcb82803d94cf53e4e52c9cf12a860fb
Ignore-AOSP-First: this is an automerge
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>