threadId property represents a thread
id to filter out messages.
var id = instanceOfMozSmsFilter.threadId = numberValue;
A number or
This is a non-standard implementation, but it is discussed at W3C as part of the System Application Working Group.
|Messaging API||Editor's Draft||Editor Draft (WIP).|
For obvious reasons, support is primarily expected on mobile browsers.
Supported in Firefox OS 1.0.1.