Merge "Revert "libprocessgroup: return false on failure"" am: a2b180ab

Original change: https://android-review.googlesource.com/c/platform/system/core/+/2061121



Change-Id: I2af7c348c7ebbe07337f92ed514c1b444affc993
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>