Bug 174555 [DataBinding] Run validation on binding construction
When a binding is created the assumption is that the UI is synchronized with the model. This means that the UI should reflect the state of the model's validity as well. In order to ensure that the UI reflects the model's validity the consumer needs to force a copy to model on instantiation of every binding. We need to remove this requirement.
bundles/org.eclipse.core.databinding/src/org/eclipse/core/databinding/DataBindingContext.java
IObservableList modelObservableList, BindSpec bindSpec) {
		if (bindSpec == null) {
			bindSpec = new DefaultBindSpec();
		}
		Binding result = new ListBinding(targetObservableList,
				modelObservableList, bindSpec);
		result.init(this);
		return result;
	}
	/**
	 * Disposes of this data binding context and all bindings that were added to
	 * this context.
	 */
	public void dispose() {
		Binding[] bindingArray = (Binding[]) bindings.toArray(new Binding[bindings.size()]);
		for (int i = 0; i < bindingArray.length; i++) {
			bindingArray[i].dispose();
		}
	}
	/**
	 * Fires a binding event to all binding listeners. To be called by bindings
	 * in this data binding context.
	 * 
	 * @param event
	 * @return a status object  
	 */
	protected IStatus fireBindingEvent(BindingEvent event) {
		IStatus result = Status.OK_STATUS;
		for (Iterator bindingEventIter = bindingEventListeners.iterator(); bindingEventIter
				.hasNext();) {