Bug 182714 [Contributions] Improve toolbar configurability
bundles/org.eclipse.jface/src/org/eclipse/jface/action/ContributionManager.java
public void insertBefore(String ID, IAction action) {
		insertBefore(ID, new ActionContributionItem(action));
	}
	/*
	 * (non-Javadoc) Method declared on IContributionManager.
	 */
	public void insertBefore(String ID, IContributionItem item) {
		IContributionItem ci = find(ID);
		if (ci == null) {
			throw new IllegalArgumentException("can't find ID " + ID);
		}
		int ix = contributions.indexOf(ci);
		if (ix >= 0) {
			
			if (allowItem(item)) {
				contributions.add(ix, item);
				itemAdded(item);
			}
		}
	}
	/*
	 * (non-Javadoc) Method declared on IContributionManager.
	 */
	public boolean isDirty() {
		if (isDirty) {
			return true;
		}
		if (hasDynamicItems()) {
			for (Iterator iter = contributions.iterator(); iter.hasNext();) {
				IContributionItem item = (IContributionItem) iter.next();