When developer options switch is off, a user including guest user
can still configure media transcoding settings via slices.
Bug: 244569778
Test: manual
Change-Id: I3d70045c2498e683bf615cbe521e2f98d50b7eec
(cherry picked from commit a94e8d0bc7)
This is to provide users with control over whether to disable
transcoding cache or not.
By default we keep the transcoding cache enabled.
The controller resides within the Media transcoding settings under
Developer Options.
Test: Manual. Unit tests added.
Bug: 185246580
Change-Id: I5cc85e4a254c87b5c84c32a303e8294c918748c2