onEnterFullscreen  
  fun onEnterFullscreen(connectFlags: <Error class: unknown class> = ConnectFlags(0u), handler: () -> Boolean): <Error class: unknown class>(source)
Emitted when JavaScript code calls 
Parameters
connectFlags 
a combination of ConnectFlags
handler
the Callback to connect. Returns true to stop other handlers from being invoked for the event. false to continue emission of the event.