Removed unused OnMenuPopup event from TWBUIMgr and renamed original OnMenuPopupEx as OnMenuPopup.
Modified implementing and calling code re changes.
*** This is a copy of change applied to trunk at r2189 and was made to make copying over of code that fixes bug #3556713 easier.
Authored by: delphidabbler 2012-08-13
Parent: [r2190]
Child: [r2192]
