Merge "Reapply "libprocessgroup: Remove __BEGIN_DECLS and __END_DECLS"" into main am: b053403046 am: 45a4b6f511

Original change: https://android-review.googlesource.com/c/platform/system/core/+/3369297

Change-Id: I61af986984581c61be71fdaa7874b0e2ba1a53fb
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>