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
parent = renderer.getUIContainer(element);
				}
			}
		}
		
		IEclipseContext parentContext = null;
		if (element.getCurSharedRef() != null) {
			MPlaceholder ph = element.getCurSharedRef();
			parentContext = getContext(ph.getParent());
		} else if (parentContext == null && element.getParent() != null) {
			parentContext = getContext(element.getParent());
		} else if (parentContext == null && element.getParent() == null) {
			parentContext = getContext((MUIElement) ((EObject) element)
					.eContainer());
		}
		return createGui(element, parent, parentContext);
	}
	private Shell getLimboShell() {
		if (limbo == null) {
			limbo = new Shell(Display.getCurrent(), SWT.NONE);
			limbo.setBackgroundMode(SWT.INHERIT_DEFAULT);
			limbo.setData(ShellActivationListener.DIALOG_IGNORE_KEY,
					Boolean.TRUE);
		}
		return limbo;
	}
	/**
	 * @param element
	 */
	public void removeGui(final MUIElement element) {