Bug 81078 [preferences] Restore Defaults duplicates list entries
I200412142000 Restore Defaults on Java > Editor > Appearance duplicates the "Appearance color options" entries.
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/preferences/AbstractConfigurationBlock.java
* List of master/slave listeners when there's a dependency.
	 * 
	 * @see #createDependency(Button, Control)
	 * @since 3.0
	 */
	private ArrayList fMasterSlaveListeners= new ArrayList();
	
	private StatusInfo fStatus;
	private final PreferencePage fMainPage;
	public AbstractConfigurationBlock(OverlayPreferenceStore store) {
		Assert.isNotNull(store);
		fStore= store;
		fMainPage= null;
	}
	
	public AbstractConfigurationBlock(OverlayPreferenceStore store, PreferencePage mainPreferencePage) {
		Assert.isNotNull(store);
		Assert.isNotNull(mainPreferencePage);
		fStore= store;
		fMainPage= mainPreferencePage;
	}
	protected final ScrolledPageContent getParentScrolledComposite(Control control) {
		Control parent= control.getParent();
		while (!(parent instanceof ScrolledPageContent) && parent != null) {
			parent= parent.getParent();
		}
		if (parent instanceof ScrolledPageContent) {
			return (ScrolledPageContent) parent;
		}
		return null;