Aehm...wait.
Where did you find that Blizzard added those conditions? Do you have any source of information?
Lua Code:
"HasVehicleActionBar", "HasOverrideActionBar", "HasTempShapeshiftActionBar",
"HasOverrideUI", "GetVehicleBarIndex", "GetOverrideBarIndex",
"HasExtraActionBar", "GetTempShapeshiftBarIndex", "CanExitVehicle"
So I could basically rewrite this
Lua Code:
RegisterStateDriver(frame, "visibility", "[petbattle][overridebar][vehicleui][possessbar,@vehicle,exists] hide; show")
to
Lua Code:
RegisterStateDriver(frame, "visibility", "[petbattle][HasOverrideUI] hide; show")
The caveat is that "HasOverrideUI" has to return true on every single occasion where the OverrideActionBar is shown. (Means the main actionbar got swapped out and the override actionbar got swapped in). The problem we had till now is that vehicleui, overridebar and possessbar fired under certain situation while actually showing the OverrideActionBar.
Need to test this with Phanx's macro.
Lua Code:
/run local s=SecureCmdOptionParse print(s("[extrabar]extrabar"),s("[overridebar]overridebar"),s("[possessbar]possessbar"),s("[vehicleui]vehicleui"))
http://wowprogramming.com/docs/api/SecureCmdOptionParse
------------
Regarding UnitAura change.
Are you kidding on that? Why would they have removed value1, value2 and value3 returns? Any aura value tracker now relies on those values.