Bug 118429 [DataBinding] Validation should use IStatus, not just Strings
In order to use data binding in Workbench or IDE dialogs and preference pages, we need validation in terms of IStatus objects. Using strings is too simplistic. For example, look at the wizard for creating a new class. You will get a warning if the class name does not start with an uppercase letter, or if you don't provide a package name, but you will still be able to click "Finish" to proceed anyway. (Note that IStatus is currently not on the classpath, we need to re-introduce the dependency on org.eclipse.equinox.common, which contains IStatus etc.)
bundles/org.eclipse.core.databinding.observable/src/org/eclipse/core/databinding/observable/Diffs.java
public Set getRemovals() {
				return unmodifiableRemovals;
			}
		};
	}
	/**
	 * @param difference
	 * @return a list diff with one differing entry
	 */
	public static ListDiff createListDiff(ListDiffEntry difference) {
		return createListDiff(new ListDiffEntry[] { difference });
	}
	/**
	 * @param difference1
	 * @param difference2
	 * @return a list diff with two differing entries
	 */
	public static ListDiff createListDiff(ListDiffEntry difference1,
			ListDiffEntry difference2) {
		return createListDiff(new ListDiffEntry[] { difference1, difference2 });
	}
	/**
	 * @param differences
	 * @return a list diff with the given entries
	 */
	public static ListDiff createListDiff(final ListDiffEntry[] differences) {
		return new ListDiff() {
			public ListDiffEntry[] getDifferences() {
				return differences;
			}