Merge "Revert "Revert "Remove cutils threads.h header completely.""" into main am: c05fd258ee am: 37f0b26947 am: 604233aaee am: 07929cad36 am: c6fcc48f44

Original change: https://android-review.googlesource.com/c/platform/system/core/+/2713394

Change-Id: I06ab8d5dfa1bc1f4df749d1535c0557727a99c18
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>