EntropyMixer is designed to be triggered in two ways, as either the result of a self-set timer or of one of three system broadcasts. It is not meant to be triggered in any other way, so exposing it via servicemanager is undesirable. Bug: 18106000 Cherry-pick of commit: 9287e0dd272b85b475e33bcbd7d868517a0f98f9 Change-Id: I9aeb35e7ffde75090f4234ea193514fb883b1425