Merge "add a folder for adding unit tests for app functions" into main am: db99864fc6

Original change: https://android-review.googlesource.com/c/platform/frameworks/base/+/3252197

Change-Id: Ib95a8e34b7e6f5900a4cc85c2c3a2be67dd62265
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>