      * This class could return the full data immediately. We don't, because real DB-backed code won't.
      */
     var nullModel: BookmarksModel {
-        let f = MemoryBookmarkFolder(id: "root", name: "Root", children: [])
+        let f = MemoryBookmarkFolder(id: BookmarkRoots.PLACES_FOLDER_GUID, name: "Root", children: [])
         return BookmarksModel(modelFactory: self, root: f)
     }
 

            res.append(BookmarkItem(id: Bytes.generateGUID(), title: "Title \(i)", url: "http://www.example.com/\(i)"))
        }

        mobile = MemoryBookmarkFolder(id: "mobile", name: "Mobile Bookmarks", children: res)

        unsorted = MemoryBookmarkFolder(id: "unsorted", name: "Unsorted Bookmarks", children: [])
        sink = MemoryBookmarksSink()

        root = MemoryBookmarkFolder(id: "root", name: "Root", children: [mobile, unsorted])
    }

    func modelForFolder(folder: BookmarkFolder, success: (BookmarksModel) -> (), failure: (Any) -> ()) {

import Foundation

import UIKit

public struct BookmarkRoots {
    // These are stolen from Fennec's BrowserContract.
    static let MOBILE_FOLDER_GUID = "mobile"
    static let PLACES_FOLDER_GUID = "places"
    static let MENU_FOLDER_GUID = "menu"
    static let TAGS_FOLDER_GUID = "tags"
    static let TOOLBAR_FOLDER_GUID = "toolbar"
    static let UNFILED_FOLDER_GUID = "unfiled"
    static let FAKE_DESKTOP_FOLDER_GUID = "desktop"
    static let PINNED_FOLDER_GUID = "pinned"
}

/**
 * The immutable base interface for bookmarks and folders.
