skins2: add a way to hide Video/Audio/Misc popupmenus

when one of these three popupmenus is shown, there was no way to hide it
 without first executing an item in the menu. (see for instance, earthox skin)

This patch ensures that the usual way to hide the default PopupMenu is also
used to hide any one of these other three popupmenus.

modules/gui/skins2/controls/ctrl_image.cpp

@@ -60,6 +60,9 @@ void CtrlImage::handleEvent( EvtGeneric &rEvent )
     else if( rEvent.getAsString() == "mouse:left:up:none" )
     {
         CmdDlgHidePopupMenu( getIntf() ).execute();
+        CmdDlgHideVideoPopupMenu( getIntf() ).execute();
+        CmdDlgHideAudioPopupMenu( getIntf() ).execute();
+        CmdDlgHideMiscPopupMenu( getIntf() ).execute();
     }
     else if( rEvent.getAsString() == "mouse:left:dblclick:none" )
     {