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

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

Change-Id: Ibb840661bc1da728cfd9973c87c59b14a6b044b8
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>