libprocessgroup: Do not remove uid cgroups directory am: cc25244b77

Original change: https://googleplex-android-review.googlesource.com/c/platform/system/core/+/15179851

Change-Id: Ibc68992142f74109271deea28dda436e3f94fa7f

libprocessgroup/processgroup.cpp

@@ -146,12 +146,6 @@ static int RemoveProcessGroup(const char* cgroup, uid_t uid, int pid, unsigned i
         std::this_thread::sleep_for(5ms);
     }
 
-    // With the exception of boot or shutdown, system uid_ folders are always populated. Spinning
-    // here would needlessly delay most pid removals. Additionally, once empty a uid_ cgroup won't
-    // have processes hanging on it (we've already spun for all its pid_), so there's no need to
-    // spin anyway.
-    rmdir(uid_path.c_str());
-
     return ret;
 }