The nsIDOMMessageEvent interface is used for server-sent events and for
 cross-domain messaging.

 For more information on this interface, please see
 http://www.whatwg.org/specs/web-apps/current-work/#messageevent
[scriptable, uuid(98150805-6a15-4667-815a-1a8c87cb4bbc)]
interface nsIDOMMessageEvent : nsIDOMEvent

Attributes

 Custom string data associated with this event.
readonly attribute DOMString data
 The last event ID string of the event source, for server-sent DOM events; this
 value is the empty string for cross-origin messaging.
readonly attribute DOMString lastEventId
 The origin of the site from which this event originated, which is the
 scheme, ":", and if the URI has a host, "//" followed by the
 host, and if the port is not the default for the given scheme,
 ":" followed by that port.  This value does not have a trailing slash.
readonly attribute DOMString origin
 The window which originated this event.
readonly attribute nsIDOMWindow source

Methods

 Initializes this event with the given data, in a manner analogous to
 the similarly-named method on the nsIDOMEvent interface, also setting the
 data, origin, source, and lastEventId attributes of this appropriately.
void initMessageEvent(in DOMString aType, in boolean aCanBubble, in boolean aCancelable, in DOMString aData, in DOMString aOrigin, in DOMString aLastEventId, in nsIDOMWindow aSource)
 Initializes this event with the given data, in a manner analogous to
 the similarly-named method on the Event interface, also setting the data,
 origin, source, and lastEventId attributes of this appropriately.
void initMessageEventNS(in DOMString aNamespaceURI, in DOMString aType, in boolean aCanBubble, in boolean aCancelable, in DOMString aData, in DOMString aOrigin, in DOMString aLastEventId, in nsIDOMWindow aSource)