Bug 898308 - Clean up SessionStore initialization; f=smacleod, r=dao

browser/base/content/browser.js

@@ -137,6 +137,9 @@ XPCOMUtils.defineLazyModuleGetter(this, "PrivateBrowsingUtils",
 XPCOMUtils.defineLazyModuleGetter(this, "SitePermissions",
   "resource:///modules/SitePermissions.jsm");
 
+XPCOMUtils.defineLazyModuleGetter(this, "SessionStore",
+  "resource:///modules/sessionstore/SessionStore.jsm");
+
 let gInitialPages = [
   "about:blank",
   "about:newtab",
@@ -1033,6 +1036,7 @@ var gBrowserInit = {
     OfflineApps.init();
     IndexedDBPromptHelper.init();
     gFormSubmitObserver.init();
+    SocialUI.init();
     AddonManager.addAddonListener(AddonsMgrListener);
     WebrtcIndicator.init();
 
@@ -1091,10 +1095,6 @@ var gBrowserInit = {
       NP.trackBrowserWindow(window);
     }
 
-    // initialize the session-restore service (in case it's not already running)
-    let ss = Cc["@mozilla.org/browser/sessionstore;1"].getService(Ci.nsISessionStore);
-    let ssPromise = ss.init(window);
-
     PlacesToolbarHelper.init();
 
     ctrlTab.readPref();
@@ -1270,14 +1270,13 @@ var gBrowserInit = {
 #endif
 #endif
 
-    ssPromise.then(() =>{
+    SessionStore.promiseInitialized.then(() => {
       // Enable the Restore Last Session command if needed
-      if (ss.canRestoreLastSession &&
+      if (SessionStore.canRestoreLastSession &&
           !PrivateBrowsingUtils.isWindowPrivate(window))
         goSetCommandEnabled("Browser:RestoreLastSession", true);
 
       TabView.init();
-      SocialUI.init();
 
       setTimeout(function () { BrowserChromeTest.markAsReady(); }, 0);
     });

browser/base/content/test/social/browser_social_window.js

@@ -17,7 +17,6 @@ function resetSocial() {
 }
 
 let createdWindows = [];
-let ss = Cc["@mozilla.org/browser/sessionstore;1"].getService(Ci.nsISessionStore);
 
 function openWindowAndWaitForInit(callback) {
   // this notification tells us SocialUI.init() has been run...
@@ -27,12 +26,7 @@ function openWindowAndWaitForInit(callback) {
   Services.obs.addObserver(function providerSet(subject, topic, data) {
     Services.obs.removeObserver(providerSet, topic);
     info(topic + " observer was notified - continuing test");
-    // We need to wait for the SessionStore as well, since
-    // SocialUI.init() is also waiting on it.
-    ss.init(w).then(function () {
-      executeSoon(function() {callback(w);});
-    });
-
+    executeSoon(() => callback(w));
   }, topic, false);
 }
 

browser/components/nsBrowserGlue.js

@@ -68,6 +68,9 @@ XPCOMUtils.defineLazyModuleGetter(this, "PlacesBackups",
 XPCOMUtils.defineLazyModuleGetter(this, "OS",
                                   "resource://gre/modules/osfile.jsm");
 
+XPCOMUtils.defineLazyModuleGetter(this, "SessionStore",
+                                  "resource:///modules/sessionstore/SessionStore.jsm");
+
 const PREF_PLUGINS_NOTIFYUSER = "plugins.update.notifyUser";
 const PREF_PLUGINS_UPDATEURL  = "plugins.update.url";
 
@@ -173,7 +176,7 @@ BrowserGlue.prototype = {
         this._finalUIStartup();
         break;
       case "browser-delayed-startup-finished":
-        this._onFirstWindowLoaded();
+        this._onFirstWindowLoaded(subject);
         Services.obs.removeObserver(this, "browser-delayed-startup-finished");
         break;
       case "sessionstore-windows-restored":
@@ -579,7 +582,7 @@ BrowserGlue.prototype = {
   },
 
   // the first browser window has finished initializing
-  _onFirstWindowLoaded: function BG__onFirstWindowLoaded() {
+  _onFirstWindowLoaded: function BG__onFirstWindowLoaded(aWindow) {
 #ifdef XP_WIN
     // For windows seven, initialize the jump list module.
     const WINTASKBAR_CONTRACTID = "@mozilla.org/windows-taskbar;1";
@@ -591,6 +594,7 @@ BrowserGlue.prototype = {
     }
 #endif
 
+    SessionStore.init(aWindow);
     this._trackSlowStartup();
 
     // Offer to reset a user's profile if it hasn't been used for 60 days.

browser/components/sessionstore/nsISessionStore.idl

@@ -25,14 +25,9 @@ interface nsIDOMNode;
  * |gBrowser.tabContainer| such as e.g. |gBrowser.selectedTab|.
  */
 
-[scriptable, uuid(092fa0cc-e99b-11e2-a2a3-a25b4f45d8e2)]
+[scriptable, uuid(700756cc-f5c7-11e2-b842-59d9dc830245)]
 interface nsISessionStore : nsISupports
 {
-  /**
-   * Initialize the service
-   */
-  jsval init(in nsIDOMWindow aWindow);
-
   /**
    * Is it possible to restore the previous session. Will always be false when
    * in Private Browsing mode.

browser/components/sessionstore/src/SessionStore.jsm

@@ -142,7 +142,7 @@ function debug(aMsg) {
 
 this.SessionStore = {
   get promiseInitialized() {
-    return SessionStoreInternal.promiseInitialized.promise;
+    return SessionStoreInternal.promiseInitialized;
   },
 
   get canRestoreLastSession() {
@@ -154,7 +154,7 @@ this.SessionStore = {
   },
 
   init: function ss_init(aWindow) {
-    return SessionStoreInternal.init(aWindow);
+    SessionStoreInternal.init(aWindow);
   },
 
   getBrowserState: function ss_getBrowserState() {
@@ -340,7 +340,7 @@ let SessionStoreInternal = {
   _deferredInitialState: null,
 
   // A promise resolved once initialization is complete
-  _promiseInitialization: Promise.defer(),
+  _deferredInitialized: Promise.defer(),
 
   // Whether session has been initialized
   _sessionInitialized: false,
@@ -363,7 +363,7 @@ let SessionStoreInternal = {
    * A promise fulfilled once initialization is complete.
    */
   get promiseInitialized() {
-    return this._promiseInitialization;
+    return this._deferredInitialized.promise;
   },
 
   /* ........ Public Getters .............. */
@@ -378,31 +378,44 @@ let SessionStoreInternal = {
     this._lastSessionState = null;
   },
 
-  /* ........ Global Event Handlers .............. */
-
   /**
-   * Initialize the component
+   * Initialize the sessionstore service.
    */
-  initService: function ssi_initService() {
-    if (this._sessionInitialized) {
-      return;
+  init: function (aWindow) {
+    if (this._initialized) {
+      throw new Error("SessionStore.init() must only be called once!");
     }
+
+    if (!aWindow) {
+      throw new Error("SessionStore.init() must be called with a valid window.");
+    }
+
     TelemetryTimestamps.add("sessionRestoreInitialized");
     OBSERVING.forEach(function(aTopic) {
       Services.obs.addObserver(this, aTopic, true);
     }, this);
 
     this._initPrefs();
-
+    this._initialized = true;
     this._disabledForMultiProcess = this._prefBranch.getBoolPref("tabs.remote");
 
     // this pref is only read at startup, so no need to observe it
     this._sessionhistory_max_entries =
       this._prefBranch.getIntPref("sessionhistory.max_entries");
 
-    gSessionStartup.onceInitialized.then(
-      this.initSession.bind(this)
-    );
+    // Wait until nsISessionStartup has finished reading the session data.
+    gSessionStartup.onceInitialized.then(() => {
+      // Parse session data and start restoring.
+      this.initSession();
+
+      // Start tracking the given (initial) browser window.
+      if (!aWindow.closed) {
+        this.onLoad(aWindow);
+      }
+
+      // Let everyone know we're done.
+      this._deferredInitialized.resolve();
+    });
   },
 
   initSession: function ssi_initSession() {
@@ -492,7 +505,6 @@ let SessionStoreInternal = {
     this._performUpgradeBackup();
 
     this._sessionInitialized = true;
-    this._promiseInitialization.resolve();
   },
 
   /**
@@ -565,36 +577,19 @@ let SessionStoreInternal = {
     });
   },
 
-  /**
-   * Start tracking a window.
-   *
-   * This function also initializes the component if it is not
-   * initialized yet.
-   */
-  init: function ssi_init(aWindow) {
-    if (!aWindow) {
-      throw new Error("init() must be called with a valid window.");
-    }
-
-    let self = this;
-    this.initService();
-    return this._promiseInitialization.promise.then(
-      function onSuccess() {
-        if (!aWindow.closed) {
-          self.onLoad(aWindow);
-        }
-      }
-    );
-  },
-
   /**
    * Called on application shutdown, after notifications:
    * quit-application-granted, quit-application
    */
   _uninit: function ssi_uninit() {
+    if (!this._initialized) {
+      throw new Error("SessionStore is not initialized.");
+    }
+
     // save all data for session resuming
-    if (this._sessionInitialized)
+    if (this._sessionInitialized) {
       this.saveState(true);
+    }
 
     // clear out priority queue in case it's still holding refs
     TabRestoreQueue.reset();

browser/components/sessionstore/test/head.js

@@ -382,13 +382,11 @@ let TestRunner = {
   run: function () {
     waitForExplicitFinish();
 
-    SessionStore.promiseInitialized.then(function () {
-      executeSoon(function () {
-        this.backupState = JSON.parse(ss.getBrowserState());
-        this._iter = runTests();
-        this.next();
-      }.bind(this));
-    }.bind(this));
+    SessionStore.promiseInitialized.then(() => {
+      this.backupState = JSON.parse(ss.getBrowserState());
+      this._iter = runTests();
+      this.next();
+    });
   },
 
   /**