AppUpdateType Identifiers for the different types of developer triggered updates. 
InstallErrorCode StatusCodes used by InstallService. 
InstallStatus Status of a download / install. 
UpdateAvailability Availability of an update for the requested package. 
UpdatePrecondition Conditions related to an available update that may prevent the immediate execution of certain AppUpdateTypes. 


ActivityResult Custom Activity results for the in-app update flow.