Add a method to load vendor_service_context only. am: 4b5cfdcd0a  -s ours am: 5bea192056  -s ours am: 6eb87ccb1b  -s ours
am: f837f975d2  -s ours

Change-Id: I0b848b15e0308181a159a4054f95ee4f47a4f9b6