Emulator host will set the guest keyboard layout with boot
properties based on the host keyboard layout.
Also, fixed complaints in setting properties adb_enabled and
install_non_market_apps.
BUG: 78115103
Change-Id: Iad3750af5383ba27fbf20eb9b26652f037853f1f
Signed-off-by: Weilun Du <wdu@google.com>