Disable immersive mode confirmation for test automation

PolicyControl#disableImmersiveConfirmation to return true as
long as test harness flag is set.

Test harness flag is read via ro.test_harness, and can only be
set to true on builds with root access

Change-Id: I5c2d56e8ea4d5a2972ab42e9a98eb2fce52b11ee
1 file changed