Android.permission.remove_tasks : Permission Denied

I want to remove recent task list. Through googling I have found some links from stackoverflow. But none of them has been properly answered. Only one link Android, how to clear th

Solution 1:

android.permission.REMOVE_TASKS is denied

That permission is a signature-level permission. You will only be able to use it if your app is signed by the same signing key as the device firmware.