Bug 1126184: Part 3: Mochitest fixes for suggested tiles.

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

@@ -9,6 +9,7 @@
  */
 function runTests() {
   requestLongerTimeout(2);
+  yield addNewTabPageTab();
 
   // test a simple drag-and-drop scenario
   yield setLinks("0,1,2,3,4,5,6,7,8");

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

@@ -13,6 +13,7 @@ const PREF_NEWTAB_COLUMNS = "browser.newtabpage.columns";
  */
 function runTests() {
   registerCleanupFunction(_ => Services.prefs.clearUserPref(PREF_NEWTAB_COLUMNS));
+  yield addNewTabPageTab();
 
   // drag a new site onto the very first cell
   yield setLinks("0,1,2,3,4,5,6,7,8");

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

@@ -6,6 +6,8 @@
  * dragging them around.
  */
 function runTests() {
+  yield addNewTabPageTab();
+
   // the first three sites are pinned - make sure they're re-arranged correctly
   yield setLinks("0,1,2,3,4,5,6,7,8");
   setPinnedLinks("0,1,2,,,5");

browser/modules/DirectoryLinksProvider.jsm

@@ -531,6 +531,12 @@ let DirectoryLinksProvider = {
   _updateRelatedTile: function() {
     let sortedLinks = NewTabUtils.getProviderLinks(this);
 
+    if (!sortedLinks) {
+      // If NewTabUtils.links.resetCache() is called before getting here,
+      // sortedLinks may be undefined.
+      return;
+    }
+
     // Delete the current related tile, if one exists.
     let initialLength = sortedLinks.length;
     this.maxNumLinks = initialLength;

toolkit/modules/NewTabUtils.jsm

@@ -936,7 +936,7 @@ let Links = {
     // Build a list containing a copy of each provider's sortedLinks list.
     let linkLists = [];
     for (let links of this._providers.values()) {
-      if (links) {
+      if (links && links.sortedLinks) {
         linkLists.push(links.sortedLinks.slice());
       }
     }