- stop sharing from the screen share toolbar button.

...rg/bigbluebutton/app/screenshare/red5/Red5AppHandler.java

...tton/modules/screenshare/events/ScreenSharePausedEvent.as

...button/modules/screenshare/managers/ScreenshareManager.as

...tton/modules/screenshare/managers/ToolbarButtonManager.as

...luebutton/modules/screenshare/services/MessageReceiver.as

...screenshare/view/components/ScreensharePublishWindow.mxml

...on/modules/screenshare/view/components/ToolbarButton.mxml