Protect AppListItemList Add/Remove and fix sync bugs

ui/app_list/app_list_item_list.h

 // Copyright (c) 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef UI_APP_LIST_APP_LIST_ITEM_LIST_H_
 #define UI_APP_LIST_APP_LIST_ITEM_LIST_H_
 
 #include <string>
 
 #include "base/memory/scoped_ptr.h"
@@ skipping 19 matching lines @@
   void RemoveObserver(AppListItemListObserver* observer);
 
   // Finds item matching |id|. NOTE: Requires a linear search.
   AppListItem* FindItem(const std::string& id);
 
   // Finds the |index| of the the item matching |id| in |app_list_items_|.
   // Returns true if the matching item is found.
   // Note: Requires a linear search.
   bool FindItemIndex(const std::string& id, size_t* index);
 
+  // Moves item at |from_index| to |to_index|.
+  // Triggers observers_.OnListItemMoved().
+  void MoveItem(size_t from_index, size_t to_index);
+
+  // Sets the position of |item| which is expected to be a member of
+  // |app_list_items_| and sorts the list accordingly.
+  void SetItemPosition(AppListItem* item,
+                       const syncer::StringOrdinal& new_position);
+
+  AppListItem* item_at(size_t index) {
+    DCHECK_LT(index, app_list_items_.size());
+    return app_list_items_[index];
+  }
+  const AppListItem* item_at(size_t index) const {
+    DCHECK_LT(index, app_list_items_.size());
+    return app_list_items_[index];
+  }
+  size_t item_count() const { return app_list_items_.size(); }
+
+ private:
+  friend class AppListItemListTest;
+  friend class AppListModel;
+  friend class AppListModelTest;  // TODO(stevenjb): Remove dependency
+
   // Adds |item| to the end of |app_list_items_|. Takes ownership of |item|.
   // Triggers observers_.OnListItemAdded(). Returns the index of the added item.
   size_t AddItem(AppListItem* item);
 
-  // Inserts |item| at the |index| into |app_list_items_|. Takes ownership of
-  // |item|. Triggers observers_.OnListItemAdded().
-  void InsertItemAt(AppListItem* item, size_t index);
-
   // Finds item matching |id| in |app_list_items_| (linear search) and deletes
   // it. Triggers observers_.OnListItemRemoved() after removing the item from
   // the list and before deleting it.
   void DeleteItem(const std::string& id);
 
-  // Deletes all items matching |type| which must be a statically defined
-  // type descriptor, e.g. AppListFolderItem::kItemType. If |type| is NULL,
-  // deletes all items. Triggers observers_.OnListItemRemoved() for each item
-  // as for DeleteItem.
-  void DeleteItemsByType(const char* type);
-
   // Removes the item with matching |id| in |app_list_items_| without deleting
   // it. Returns a scoped pointer containing the removed item.
   scoped_ptr<AppListItem> RemoveItem(const std::string& id);
 
   // Removes the item at |index| from |app_list_items_| without deleting it.
   // Returns a scoped pointer containing the removed item.
   scoped_ptr<AppListItem> RemoveItemAt(size_t index);
 
-  // Moves item at |from_index| to |to_index|.
-  // Triggers observers_.OnListItemMoved().
-  void MoveItem(size_t from_index, size_t to_index);
-
-  // Sets the position of |item| which is expected to be a member of
-  // |app_list_items_| and sorts the list accordingly.
-  void SetItemPosition(AppListItem* item,
-                       const syncer::StringOrdinal& new_position);
-
-  AppListItem* item_at(size_t index) {
-    DCHECK_LT(index, app_list_items_.size());
-    return app_list_items_[index];
-  }
-  size_t item_count() const { return app_list_items_.size(); }
-
- private:
   // Deletes item at |index| and signals observers.
   void DeleteItemAt(size_t index);
 
   // If |item|->position() is not a valid ordinal, sets |item|->position()
   // to a valid ordinal after the last item in the list.
   void EnsureValidItemPosition(AppListItem* item);
 
   // Returns the index at which to insert an item in |app_list_items_| based on
   // |position| (which must be valid) and |id| (if the positions are equal).
   size_t GetItemSortOrderIndex(const syncer::StringOrdinal& position,
                                const std::string& id);
 
   ScopedVector<AppListItem> app_list_items_;
   ObserverList<AppListItemListObserver> observers_;
 
   DISALLOW_COPY_AND_ASSIGN(AppListItemList);
 };
 
 }  // namespace app_list
 
 #endif  // UI_APP_LIST_APP_LIST_ITEM_LIST_H_