Bug 63420 [R21PRES] Flash on tab switch
bundles/org.eclipse.ui.presentations.r21/src/org/eclipse/ui/internal/presentations/R21BasicStackPresentation.java
showSystemMenu(globalPos);
			}
		}
	};
	private Listener menuListener = new Listener() {
		/*
		 * (non-Javadoc)
		 * 
		 * @see org.eclipse.swt.widgets.Listener#handleEvent(org.eclipse.swt.widgets.Event)
		 */
		public void handleEvent(Event event) {
			Point pos = new Point(event.x, event.y);
			showSystemMenu(pos);
		}
	};
	private Listener dragListener = new Listener() {
		public void handleEvent(Event event) {
			Point localPos = new Point(event.x, event.y);
			CTabItem tabUnderPointer = paneFolder.getItem(localPos);
			
			if (tabUnderPointer == null) {
				if (paneFolder.getTabPosition() == SWT.BOTTOM
						&& localPos.y < paneFolder.getControl().getBounds().height
								- paneFolder.getTabHeight())
					tabUnderPointer = paneFolder.getSelection();
				else if (paneFolder.getTabPosition() == SWT.TOP
						&& localPos.y > paneFolder.getTabHeight())
					tabUnderPointer = paneFolder.getSelection();
			}