Bug 120544 [build path] Editing external source folder does not persist
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/wizards/buildpaths/SourceContainerWorkbookPage.java
}				
			} else if (index == IDX_EDIT) {
				editEntry();
			} else if (index == IDX_REMOVE) {
				removeEntry();
			}
		}
	}
	private void editEntry() {
		List selElements= fFoldersList.getSelectedElements();
		if (selElements.size() != 1) {
			return;
		}
		Object elem= selElements.get(0);
		if (fFoldersList.getIndexOfElement(elem) != -1) {
			editElementEntry((CPListElement) elem);
		} else if (elem instanceof CPListElementAttribute) {
			editAttributeEntry((CPListElementAttribute) elem);
		}
	}
	private void editElementEntry(CPListElement elem) {
		if (elem.getLinkTarget() != null) {
			removeEntry();
			CPListElement entry= openNewLinkedSourceContainerDialog(elem);
			
			if (entry == null)
				entry= elem;
			
			fFoldersList.addElement(entry);
			fFoldersList.postSetSelection(new StructuredSelection(entry));