Defined in github.com/aws/aws-sdk-go/service/swf/api.go
If set, specifies the default maximum time before which a worker processing a task of this type must report progress by calling RecordActivityTaskHeartbeat. If the timeout is exceeded, the activity task is automatically timed out. This default can be overridden when scheduling an activity task using the ScheduleActivityTask decision. If the activity worker subsequently attempts to record a heartbeat or returns a result, the activity worker receives an UnknownResource fault. In this case, Amazon SWF no longer considers the activity task to be valid; the activity worker should clean up the activity task.
The duration is specified in seconds; an integer greater than or equal to 0. The value "NONE" can be used to specify unlimited duration.