Bug 246462 [DataBinding] [Databinding] Extend ControlObservableValue to observe Size, Location, Bounds and Focus of a control
bundles/org.eclipse.jface.databinding/src/org/eclipse/jface/databinding/swt/SWTObservables.java
* @param widget
	 * @return observable value
	 * @throws IllegalArgumentException
	 *             if the type of <code>widget</code> is unsupported
	 *             
	 * @since 1.3
	 */
	public static ISWTObservableValue observeText(Widget widget) {
		if (widget instanceof Label) {
			return new LabelObservableValue((Label) widget);
		} else if (widget instanceof Link) {
			return new LinkObservableValue((Link) widget);
		} else if (widget instanceof CLabel) {
			return new CLabelObservableValue((CLabel) widget);
		} else if (widget instanceof Combo) {
			return new ComboObservableValue((Combo) widget, SWTProperties.TEXT);
		} else if (widget instanceof CCombo) {
			return new CComboObservableValue((CCombo) widget,
					SWTProperties.TEXT);
		} else if (widget instanceof Shell) {
			return new ShellObservableValue((Shell) widget);
		} else if (widget instanceof Text) {
			return new TextObservableValue((Text) widget, SWT.None);
		} else if (widget instanceof Item) {
			return new ItemObservableValue((Item)widget);
		}
		throw new IllegalArgumentException(
				"Widget [" + widget.getClass().getName() + "] is not supported."); 
	}
	/**