Bug 339573 Splitting the shared area with a part doesn't remove stale placeholders
The current code only looks for the addition of an MPlaceholder in the shared area as the hint to remove locals. When you split the area the element that gets added is the new MPartSashContainer...
bundles/org.eclipse.e4.ui.workbench.swt/src/org/eclipse/e4/ui/internal/workbench/swt/PartRenderingEngine.java
((Shell) window.getWidget()).close();
				}
			}
		} else if (testShell != null && !testShell.isDisposed()) {
			testShell.close();
		}
	}
	/*
	 * There are situations where this is called more than once until we know
	 * why this is needed we should make this safe for multiple calls
	 */
	private void cleanUp() {
		if (keyListener != null) {
			Display display = Display.getDefault();
			if (!display.isDisposed()) {
				display.removeFilter(SWT.KeyDown, keyListener);
				display.removeFilter(SWT.Traverse, keyListener);
				keyListener = null;
			}
		}
	}
	public static void initializeStyling(Display display,
			IEclipseContext appContext) {
		String cssTheme = (String) appContext.get(E4Application.THEME_ID);
		String cssURI = (String) appContext.get(E4Workbench.CSS_URI_ARG);
		if (cssTheme != null) {
			String cssResourcesURI = (String) appContext
					.get(E4Workbench.CSS_RESOURCE_URI_ARG);
			Bundle bundle = WorkbenchSWTActivator.getDefault().getBundle();
			BundleContext context = bundle.getBundleContext();