Bug 182714 [Contributions] Improve toolbar configurability
bundles/org.eclipse.jface/src/org/eclipse/jface/action/ContributionManager.java
.next();
							if (ci.isGroupMarker()) {
								break;
							}
						}
					}
					if (allowItem(item)) {
						contributions.add(i, item);
						itemAdded(item);
					}
					return;
				}
			}
		}
		throw new IllegalArgumentException("Group not found: " + groupName);
	}
	/*
	 * (non-Javadoc) Method declared on IContributionManager.
	 */
	public void appendToGroup(String groupName, IAction action) {
		addToGroup(groupName, new ActionContributionItem(action), true);
	}
	/*
	 * (non-Javadoc) Method declared on IContributionManager.
	 */
	public void appendToGroup(String groupName, IContributionItem item) {
		addToGroup(groupName, item, true);
	}
	/**
	 * This method allows subclasses of <code>ContributionManager</code> to