Bug 586555 - groupItemStorageSanity: if it's a check, let's really check it! r=tim

browser/base/content/tabview/groupitems.js

@@ -2233,12 +2233,14 @@ let GroupItems = {
   // Function: groupItemStorageSanity
   // Given persistent storage data for a groupItem, returns true if it appears to not be damaged.
   groupItemStorageSanity: function GroupItems_groupItemStorageSanity(groupItemData) {
-    // TODO: check everything
-    // Bug 586555
-    var sane = true;
-    if (!Utils.isRect(groupItemData.bounds)) {
+    let sane = true;
+    if (!groupItemData.bounds || !Utils.isRect(groupItemData.bounds)) {
       Utils.log('GroupItems.groupItemStorageSanity: bad bounds', groupItemData.bounds);
       sane = false;
+    } else if ((groupItemData.userSize && 
+               !Utils.isPoint(groupItemData.userSize)) ||
+               !groupItemData.id) {
+      sane = false;
     }
 
     return sane;