Bug 63420 [R21PRES] Flash on tab switch
bundles/org.eclipse.ui.presentations.r21/src/org/eclipse/ui/internal/presentations/R21BasicStackPresentation.java
if (part == null) {
			return null;
		}
		return part.getMenu();
	}
	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.ui.internal.skins.Presentation#dispose()
	 */
	public void dispose() {
		if (isDisposed()) {
			return;
		}
		
		paneFolder.getControl().getShell().removeShellListener(shellListener);
		PresentationUtil.removeDragListener(paneFolder.getControl(),
				dragListener);
		PresentationUtil.removeDragListener(titleLabel, dragListener);
		systemMenuManager.dispose();
		systemMenuManager.removeAll();
		paneFolder.getControl().dispose();
		paneFolder = null;
		titleLabel.dispose();
		titleLabel = null;
		viewToolBar.dispose();
	}
	/*
	 * (non-Javadoc)
	 *