Merge "Cache Unicode extension subtag key map in Zygote" into main am: 16ac7701ad am: 02bd7c0513

Original change: https://android-review.googlesource.com/c/platform/frameworks/base/+/3323077

Change-Id: Ib2d7be2c0f46bc14179326a6205050c86b2a1713
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>