diff -r 000000000000 -r 6474c204b198 browser/components/tabview/storage.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/browser/components/tabview/storage.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,201 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+// **********
+// Title: storage.js
+
+// ##########
+// Class: Storage
+// Singleton for permanent storage of TabView data.
+let Storage = {
+  GROUP_DATA_IDENTIFIER: "tabview-group",
+  GROUPS_DATA_IDENTIFIER: "tabview-groups",
+  TAB_DATA_IDENTIFIER: "tabview-tab",
+  UI_DATA_IDENTIFIER: "tabview-ui",
+
+  // ----------
+  // Function: toString
+  // Prints [Storage] for debug use
+  toString: function Storage_toString() {
+    return "[Storage]";
+  },
+
+  // ----------
+  // Function: init
+  // Sets up the object.
+  init: function Storage_init() {
+    this._sessionStore =
+      Cc["@mozilla.org/browser/sessionstore;1"].
+        getService(Ci.nsISessionStore);
+  },
+
+  // ----------
+  // Function: uninit
+  uninit: function Storage_uninit () {
+    this._sessionStore = null;
+  },
+
+  // ----------
+  // Function: saveTab
+  // Saves the data for a single tab.
+  saveTab: function Storage_saveTab(tab, data) {
+    Utils.assert(tab, "tab");
+
+    this._sessionStore.setTabValue(tab, this.TAB_DATA_IDENTIFIER,
+      JSON.stringify(data));
+  },
+
+  // ----------
+  // Function: getTabData
+  // Load tab data from session store and return it.
+  getTabData: function Storage_getTabData(tab) {
+    Utils.assert(tab, "tab");
+
+    let existingData = null;
+
+    try {
+      let tabData = this._sessionStore.getTabValue(tab, this.TAB_DATA_IDENTIFIER);
+      if (tabData != "")
+        existingData = JSON.parse(tabData);
+    } catch (e) {
+      // getTabValue will fail if the property doesn't exist.
+      Utils.log(e);
+    }
+
+    return existingData;
+  },
+
+  // ----------
+  // Function: getTabState
+  // Returns the current state of the given tab.
+  getTabState: function Storage_getTabState(tab) {
+    Utils.assert(tab, "tab");
+    let tabState;
+
+    try {
+      tabState = JSON.parse(this._sessionStore.getTabState(tab));
+    } catch (e) {}
+
+    return tabState;
+  },
+
+  // ----------
+  // Function: saveGroupItem
+  // Saves the data for a single groupItem, associated with a specific window.
+  saveGroupItem: function Storage_saveGroupItem(win, data) {
+    var id = data.id;
+    var existingData = this.readGroupItemData(win);
+    existingData[id] = data;
+    this._sessionStore.setWindowValue(win, this.GROUP_DATA_IDENTIFIER,
+      JSON.stringify(existingData));
+  },
+
+  // ----------
+  // Function: deleteGroupItem
+  // Deletes the data for a single groupItem from the given window.
+  deleteGroupItem: function Storage_deleteGroupItem(win, id) {
+    var existingData = this.readGroupItemData(win);
+    delete existingData[id];
+    this._sessionStore.setWindowValue(win, this.GROUP_DATA_IDENTIFIER,
+      JSON.stringify(existingData));
+  },
+
+  // ----------
+  // Function: readGroupItemData
+  // Returns the data for all groupItems associated with the given window.
+  readGroupItemData: function Storage_readGroupItemData(win) {
+    var existingData = {};
+    let data;
+    try {
+      data = this._sessionStore.getWindowValue(win, this.GROUP_DATA_IDENTIFIER);
+      if (data)
+        existingData = JSON.parse(data);
+    } catch (e) {
+      // getWindowValue will fail if the property doesn't exist
+      Utils.log("Error in readGroupItemData: "+e, data);
+    }
+    return existingData;
+  },
+
+  // ----------
+  // Function: readWindowBusyState
+  // Returns the current busyState for the given window.
+  readWindowBusyState: function Storage_readWindowBusyState(win) {
+    let state;
+
+    try {
+      let data = this._sessionStore.getWindowState(win);
+      if (data)
+        state = JSON.parse(data);
+    } catch (e) {
+      Utils.log("Error while parsing window state");
+    }
+
+    return (state && state.windows[0].busy);
+  },
+
+  // ----------
+  // Function: saveGroupItemsData
+  // Saves the global data for the <GroupItems> singleton for the given window.
+  saveGroupItemsData: function Storage_saveGroupItemsData(win, data) {
+    this.saveData(win, this.GROUPS_DATA_IDENTIFIER, data);
+  },
+
+  // ----------
+  // Function: readGroupItemsData
+  // Reads the global data for the <GroupItems> singleton for the given window.
+  readGroupItemsData: function Storage_readGroupItemsData(win) {
+    return this.readData(win, this.GROUPS_DATA_IDENTIFIER);
+  },
+
+  // ----------
+  // Function: saveUIData
+  // Saves the global data for the <UIManager> singleton for the given window.
+  saveUIData: function Storage_saveUIData(win, data) {
+    this.saveData(win, this.UI_DATA_IDENTIFIER, data);
+  },
+
+  // ----------
+  // Function: readUIData
+  // Reads the global data for the <UIManager> singleton for the given window.
+  readUIData: function Storage_readUIData(win) {
+    return this.readData(win, this.UI_DATA_IDENTIFIER);
+  },
+
+  // ----------
+  // Function: saveVisibilityData
+  // Saves visibility for the given window.
+  saveVisibilityData: function Storage_saveVisibilityData(win, data) {
+    this._sessionStore.setWindowValue(
+      win, win.TabView.VISIBILITY_IDENTIFIER, data);
+  },
+
+  // ----------
+  // Function: saveData
+  // Generic routine for saving data to a window.
+  saveData: function Storage_saveData(win, id, data) {
+    try {
+      this._sessionStore.setWindowValue(win, id, JSON.stringify(data));
+    } catch (e) {
+      Utils.log("Error in saveData: "+e);
+    }
+  },
+
+  // ----------
+  // Function: readData
+  // Generic routine for reading data from a window.
+  readData: function Storage_readData(win, id) {
+    var existingData = {};
+    try {
+      var data = this._sessionStore.getWindowValue(win, id);
+      if (data)
+        existingData = JSON.parse(data);
+    } catch (e) {
+      Utils.log("Error in readData: "+e);
+    }
+
+    return existingData;
+  }
+};
+