Update D8 R8 to 8.4.17-dev am: 956cd6c7f1

Original change: https://android-review.googlesource.com/c/platform/prebuilts/r8/+/2987600

Change-Id: Ic9d8eba38c1a983a4b21d1e2a6ff1cd29bae2bec
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>