Bug 73984 Editing user library jar path after path change does not work [build path]
1) Create a directory containing jar file 2) Add this jar file to a new user library 3) Rename directory from 1) 4) Update the path to jar file in user libraries (select old jar reference, select new location in browser, open -> path is not updated, but old path is still used
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/preferences/UserLibraryPreferencePage.java
setPreferenceStore(JavaPlugin.getDefault().getPreferenceStore());
		fDummyProject= getPlaceholderProject();
	
		
		setTitle(PreferencesMessages.getString("UserLibraryPreferencePage.title")); 
		setDescription(PreferencesMessages.getString("UserLibraryPreferencePage.description")); 
		noDefaultAndApplyButton();
		fDialogSettings= JavaPlugin.getDefault().getDialogSettings();
		
		UserLibraryAdapter adapter= new UserLibraryAdapter();
		String[] buttonLabels= new String[] {
				PreferencesMessages.getString("UserLibraryPreferencePage.libraries.new.button"), 
				PreferencesMessages.getString("UserLibraryPreferencePage.libraries.edit.button"), 
				PreferencesMessages.getString("UserLibraryPreferencePage.libraries.addjar.button"), 
				PreferencesMessages.getString("UserLibraryPreferencePage.libraries.remove.button"), 
				null,
				PreferencesMessages.getString("UserLibraryPreferencePage.libraries.load.button"), 
				PreferencesMessages.getString("UserLibraryPreferencePage.libraries.save.button") 
		};
		
		fLibraryList= new TreeListDialogField(adapter, buttonLabels, new CPListLabelProvider());
		fLibraryList.setLabelText(PreferencesMessages.getString("UserLibraryPreferencePage.libraries.label")); 
		
		String[] names= JavaCore.getUserLibraryNames();
		ArrayList elements= new ArrayList();
		
		for (int i= 0; i < names.length; i++) {
			IPath path= new Path(JavaCore.USER_LIBRARY_CONTAINER_ID).append(names[i]);
			try {
				IClasspathContainer container= JavaCore.getClasspathContainer(path, fDummyProject);