A snackbar shows notification, one at a time.
Inital state
Returns the current element.
Updates the model. This functions should be called regularly. The first argument is the milli seconds that passed since the last time the function was called.
Insert a message that will last for 10 seconds.
Insert a message for a specific amount of milli seconds.
Dismiss the current message.
A snackbar has a queue of Notifications, each with the amount of ms the message should be displayed