Bug 735574 - Extremely frequent leak of 1 BackstagePass, 2 Mutex, 9 ProxyListener coming from fx-team; r=dietrich

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

@@ -25,7 +25,7 @@ function runTests() {
   checkGrid("0,1,2,3,7,8,9,,");
 
   // we removed a pinned site
-  reset();
+  yield restore();
   setLinks("0,1,2,3,4,5,6,7,8");
   setPinnedLinks(",1");
 
@@ -37,7 +37,7 @@ function runTests() {
 
   // we remove the last site on the grid (which is pinned) and expect the gap
   // to be re-filled and the new site to be unpinned
-  reset();
+  yield restore();
   setLinks("0,1,2,3,4,5,6,7,8,9");
   setPinnedLinks(",,,,,,,,8");
 
@@ -49,7 +49,7 @@ function runTests() {
 
   // we remove the first site on the grid with the last one pinned. all cells
   // but the last one should shift to the left and a new site fades in
-  reset();
+  yield restore();
   setLinks("0,1,2,3,4,5,6,7,8,9");
   setPinnedLinks(",,,,,,,,8");
 

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

@@ -10,8 +10,6 @@ Cu.import("resource:///modules/NewTabUtils.jsm", tmp);
 let NewTabUtils = tmp.NewTabUtils;
 
 registerCleanupFunction(function () {
-  reset();
-
   while (gBrowser.tabs.length > 1)
     gBrowser.removeTab(gBrowser.tabs[1]);
 
@@ -57,8 +55,29 @@ let TestRunner = {
     try {
       TestRunner._iter.next();
     } catch (e if e instanceof StopIteration) {
-      finish();
+      TestRunner.finish();
     }
+  },
+
+  /**
+   * Finishes all tests and cleans up.
+   */
+  finish: function () {
+    function cleanupAndFinish() {
+      // Restore the old provider.
+      NewTabUtils.links._provider = originalProvider;
+
+      whenPagesUpdated(finish);
+      NewTabUtils.restore();
+    }
+
+    let callbacks = NewTabUtils.links._populateCallbacks;
+    let numCallbacks = callbacks.length;
+
+    if (numCallbacks)
+      callbacks.splice(0, numCallbacks, cleanupAndFinish);
+    else
+      cleanupAndFinish();
   }
 };
 
@@ -106,13 +125,11 @@ function setPinnedLinks(aLinksPattern) {
 }
 
 /**
- * Resets the lists of blocked and pinned links and clears the storage.
+ * Restore the grid state.
  */
-function reset() {
-  NewTabUtils.reset();
-
-  // Restore the old provider to prevent memory leaks.
-  NewTabUtils.links._provider = originalProvider;
+function restore() {
+  whenPagesUpdated();
+  NewTabUtils.restore();
 }
 
 /**
@@ -269,11 +286,11 @@ function simulateDrop(aDropTarget, aDragSource) {
 /**
  * Resumes testing when all pages have been updated.
  */
-function whenPagesUpdated() {
+function whenPagesUpdated(aCallback) {
   let page = {
     update: function () {
       NewTabUtils.allPages.unregister(this);
-      executeSoon(TestRunner.next);
+      executeSoon(aCallback || TestRunner.next);
     }
   };
 

browser/modules/NewTabUtils.jsm

@@ -550,7 +550,7 @@ let Links = {
    * Resets the links cache.
    */
   resetCache: function Links_resetCache() {
-    this._links = [];
+    this._links = null;
   },
 
   /**
@@ -584,13 +584,17 @@ let Links = {
  */
 let NewTabUtils = {
   /**
-   * Resets the NewTabUtils module, its links and its storage.
+   * Restores all sites that have been removed from the grid.
    */
-  reset: function NewTabUtils_reset() {
+  restore: function NewTabUtils_restore() {
     Storage.clear();
     Links.resetCache();
     PinnedLinks.resetCache();
     BlockedLinks.resetCache();
+
+    Links.populateCache(function () {
+      AllPages.update();
+    }, true);
   },
 
   allPages: AllPages,