Bug 722273 - [New Tab Page] clear internal links cache on 'browser:purge-session-history'; r=dietrich

browser/base/content/test/newtab/Makefile.in

@@ -20,6 +20,7 @@ _BROWSER_FILES = \
 	browser_newtab_reset.js \
 	browser_newtab_tabsync.js \
 	browser_newtab_unpin.js \
+	browser_newtab_bug722273.js \
 	browser_newtab_bug723102.js \
 	head.js \
 	$(NULL)

browser/base/content/test/newtab/browser_newtab_bug722273.js

@@ -0,0 +1,62 @@
+/* Any copyright is dedicated to the Public Domain.
+   http://creativecommons.org/publicdomain/zero/1.0/ */
+
+const NOW = Date.now() * 1000;
+const URL = "http://fake-site.com/";
+
+let tmp = {};
+Cu.import("resource:///modules/NewTabUtils.jsm", tmp);
+Cc["@mozilla.org/moz/jssubscript-loader;1"]
+  .getService(Ci.mozIJSSubScriptLoader)
+  .loadSubScript("chrome://browser/content/sanitize.js", tmp);
+
+let {NewTabUtils, Sanitizer} = tmp;
+
+let bhist = Cc["@mozilla.org/browser/global-history;2"]
+  .getService(Ci.nsIBrowserHistory);
+
+function runTests() {
+  clearHistory();
+  fillHistory();
+  yield addNewTabPageTab();
+
+  is(cells[0].site.url, URL, "first site is our fake site");
+
+  let page = {
+    update: function () {
+      executeSoon(TestRunner.next);
+    },
+
+    observe: function () {}
+  };
+
+  NewTabUtils.allPages.register(page);
+  yield clearHistory();
+
+  NewTabUtils.allPages.unregister(page);
+  ok(!cells[0].site, "the fake site is gone");
+}
+
+function fillHistory() {
+  let uri = makeURI(URL);
+  for (let i = 59; i > 0; i--)
+    bhist.addPageWithDetails(uri, "fake site", NOW - i * 60 * 1000000);
+}
+
+function clearHistory() {
+  let s = new Sanitizer();
+  s.prefDomain = "privacy.cpd.";
+
+  let prefs = gPrefService.getBranch(s.prefDomain);
+  prefs.setBoolPref("history", true);
+  prefs.setBoolPref("downloads", false);
+  prefs.setBoolPref("cache", false);
+  prefs.setBoolPref("cookies", false);
+  prefs.setBoolPref("formdata", false);
+  prefs.setBoolPref("offlineApps", false);
+  prefs.setBoolPref("passwords", false);
+  prefs.setBoolPref("sessions", false);
+  prefs.setBoolPref("siteSettings", false);
+
+  s.sanitize();
+}

browser/base/content/test/newtab/head.js

@@ -132,7 +132,9 @@ function addNewTabPageTab() {
       cells = cw.gGrid.cells;
 
       // Continue when the link cache has been populated.
-      NewTabUtils.links.populateCache(TestRunner.next);
+      NewTabUtils.links.populateCache(function () {
+        executeSoon(TestRunner.next);
+      });
     } else {
       TestRunner.next();
     }

browser/modules/NewTabUtils.jsm

@@ -121,8 +121,6 @@ let Storage = {
       // want any data from private browsing to show up.
       PinnedLinks.resetCache();
       BlockedLinks.resetCache();
-
-      Pages.update();
     }
   },
 
@@ -187,11 +185,6 @@ let AllPages = {
    */
   _pages: [],
 
-  /**
-   * Tells whether we already added a preference observer.
-   */
-  _observing: false,
-
   /**
    * Cached value that tells whether the New Tab Page feature is enabled.
    */
@@ -203,12 +196,7 @@ let AllPages = {
    */
   register: function AllPages_register(aPage) {
     this._pages.push(aPage);
-
-    // Add the preference observer if we haven't already.
-    if (!this._observing) {
-      this._observing = true;
-      Services.prefs.addObserver(PREF_NEWTAB_ENABLED, this, true);
-    }
+    this._addObserver();
   },
 
   /**
@@ -238,6 +226,14 @@ let AllPages = {
       Services.prefs.setBoolPref(PREF_NEWTAB_ENABLED, !!aEnabled);
   },
 
+  /**
+   * Returns the number of registered New Tab Pages (i.e. the number of open
+   * about:newtab instances).
+   */
+  get length() {
+    return this._pages.length;
+  },
+
   /**
    * Updates all currently active pages but the given one.
    * @param aExceptPage The page to exclude from updating.
@@ -264,6 +260,15 @@ let AllPages = {
     }, this);
   },
 
+  /**
+   * Adds a preference observer and turns itself into a no-op after the first
+   * invokation.
+   */
+  _addObserver: function AllPages_addObserver() {
+    Services.prefs.addObserver(PREF_NEWTAB_ENABLED, this, true);
+    this._addObserver = function () {};
+  },
+
   QueryInterface: XPCOMUtils.generateQI([Ci.nsIObserver,
                                          Ci.nsISupportsWeakReference])
 };
@@ -512,6 +517,8 @@ let Links = {
         this._links = aLinks;
         executeCallbacks();
       }.bind(this));
+
+      this._addObserver();
     }
   },
 
@@ -543,8 +550,33 @@ let Links = {
    * Resets the links cache.
    */
   resetCache: function Links_resetCache() {
-    this._links = [];
-  }
+    this._links = null;
+  },
+
+  /**
+   * Implements the nsIObserver interface to get notified about browser history
+   * sanitization.
+   */
+  observe: function Storage_observe(aSubject, aTopic, aData) {
+    // Make sure to update open about:newtab instances. If there are no opened
+    // pages we can just wait for the next new tab to populate the cache again.
+    if (AllPages.length && AllPages.enabled)
+      this.populateCache(function () { AllPages.update() }, true);
+    else
+      this._links = null;
+  },
+
+  /**
+   * Adds a sanitization observer and turns itself into a no-op after the first
+   * invokation.
+   */
+  _addObserver: function AllPages_addObserver() {
+    Services.obs.addObserver(this, "browser:purge-session-history", true);
+    this._addObserver = function () {};
+  },
+
+  QueryInterface: XPCOMUtils.generateQI([Ci.nsIObserver,
+                                         Ci.nsISupportsWeakReference])
 };
 
 /**