Merge "Add README." into main am: 06cc64d820 am: bb57f623c2 am: b625738f56

Original change: https://android-review.googlesource.com/c/platform/development/+/2843615

Change-Id: I8dda7aad48008a79c93ec6efad3b8305a9e05c6d
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>