Bug 97810 [preferences] Code template preference page buttons are not grayed out if invoked as project specific property page
3.1 RC1 Steps to reproduce: - Invoke Override Method on a project with no project-specific settings - Follow link to code template preference page -> Edit, Import, ... buttons are disabled, but not grayed out -> Toggling 'Enable project specific settings twice correctly grays out the buttons
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/wizards/dialogfields/TreeListDialogField.java
*/
	public void addElements(List elements) {
		int nElements= elements.size();
		if (nElements > 0) {
			
			ArrayList elementsToAdd= new ArrayList(nElements);
			for (int i= 0; i < nElements; i++) {
				Object elem= elements.get(i);
				if (!fElements.contains(elem)) {
					elementsToAdd.add(elem);
				}
			}
			fElements.addAll(elementsToAdd);
			if (isOkToUse(fTreeControl)) {
				fTree.add(fParentElement, elementsToAdd.toArray());
				for (int i= 0; i < elementsToAdd.size(); i++) {
					fTree.expandToLevel(elementsToAdd.get(i), fTreeExpandLevel);
				}
			}
			dialogFieldChanged();
		}
	}
	/**
	* Adds an element at a position.
	*/
	public void insertElementAt(Object element, int index) {
		if (fElements.contains(element)) {
			return;
		}
		fElements.add(index, element);