TypeError: Error #1009: Cannot access a property or method of a null object reference.
	at controller.mediator::GameMediator/onFullScreenChanged()[D:\work\MagicStory\modules\game\src\controller\mediator\GameMediator.as:179]
	at Function/http://adobe.com/AS3/2006/builtin::call()
	at org.puremvc.as3.multicore.patterns.mediator::Mediator/handleNotification()
	at Function/http://adobe.com/AS3/2006/builtin::apply()
	at org.puremvc.as3.multicore.patterns.observer::Observer/notifyObserver()
	at org.puremvc.as3.multicore.core::View/notifyObservers()
	at org.puremvc.as3.multicore.patterns.facade::Facade/notifyObservers()
	at org.puremvc.as3.multicore.patterns.facade::FacadeWithJunctions/sendNotification()
	at org.puremvc.as3.multicore.patterns.observer::Notifier/sendNotification()
	at controller.mediator::StarlingRootMediator/onStageResize()[D:\work\MagicStory\modules\game\src\controller\mediator\StarlingRootMediator.as:162]
	at flash.display::Stage/set displayState()
	at controller.mediator::FullScreenBGMediator/onToggleFullScreenRequest()[D:\work\MagicStory\modules\game\src\controller\mediator\FullScreenBGMediator.as:109]
	at Function/http://adobe.com/AS3/2006/builtin::call()
	at org.puremvc.as3.multicore.patterns.mediator::Mediator/handleNotification()
	at Function/http://adobe.com/AS3/2006/builtin::apply()
	at org.puremvc.as3.multicore.patterns.observer::Observer/notifyObserver()
	at org.puremvc.as3.multicore.core::View/notifyObservers()
	at org.puremvc.as3.multicore.patterns.facade::Facade/notifyObservers()
	at org.puremvc.as3.multicore.patterns.facade::FacadeWithJunctions/sendNotification()
	at org.puremvc.as3.multicore.patterns.observer::Notifier/sendNotification()
	at controller.mediator::MainInterfaceMediator/onChangeFullScreenState()[D:\work\MagicStory\modules\game\src\controller\mediator\MainInterfaceMediator.as:147]
	at org.osflash.signals::Signal/dispatch()
	at view.windows.elements::MIBottomPaneElements/onFullScreenClick()[D:\work\MagicStory\modules\game\src\view\windows\elements\MIBottomPaneElements.as:89]
	at org.osflash.signals::Signal/dispatch()
	at ButtonsBlockElement/onMouseClick()[D:\work\MagicStory\modules\game\src\view\windows\elements\MIBottomPaneElements.as:222]