Revert^2 "Add qemu.hw.mainkeys to system property_contexts"

509b35e5d9b72f725d17fab35ecb11b9b706a399

Bug: 180412668
Merged-In: I4067bba36613fa41e3c7a085da76cda4784753ad
Change-Id: I4067bba36613fa41e3c7a085da76cda4784753ad
6 files changed