Suspected reason for the failure is that safe_process.exe already runs in a job that does not allow breakaways.
The fix is to use a fallback - make newly created process the root of the new process group. This allows to kill process together with descendants via GenerateConsoleCtrlEvent (CTRL_BREAK_EVENT, pid)
- Allow the new process to break away from any job that this
process is part of so that it can be assigned to the new JobObject
we just created. This is safe since the new JobObject is created with
the JOB_OBJECT_LIMIT_KILL_ON_JOB_CLOSE flag, making sure it will be
terminated when the last handle to it is closed(which is owned by
this process).
