Bug 105648 [Undo] - ObjectUndoContext should match if objects are equal
bundles/org.eclipse.core.commands/src/org/eclipse/core/commands/operations/ObjectUndoContext.java
*            context
	 */
	public void removeMatch(IUndoContext context) {
		children.remove(context);
	}
	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.core.commands.operations.IUndoContext#matches(IUndoContext
	 *      context)
	 */
	public boolean matches(IUndoContext context) {
		
		if (children.contains(context))
			return true;
		
		return super.matches(context);
	}
	
	/**
	 * The string representation of this operation.  Used for debugging purposes only.
	 * This string should not be shown to an end user.
	 * 
	 * @return The string representation.
	 */
	public String toString() {
		return getLabel();
	}
}