Bug 653655 - Fix errors when opening List All Tabs menu. r=dolske

browser/base/content/browser.xul

@@ -844,9 +844,8 @@
                     key="key_tabview"
                     label="&viewTabGroups.label;"
                     command="Browser:ToggleTabView"
-                    observes="tabviewGroupsNumber"
+                    observes="tabviewGroupsNumber"/>
-                    keepme="true"/>
+          <menuseparator id="alltabs-popup-separator"/>
-          <menuseparator id="alltabs-popup-separator" keepme="true"/>
         </menupopup>
       </toolbarbutton>
 

browser/base/content/tabbrowser.xml

@@ -3738,7 +3738,12 @@
 
           var tabstripBO = tabContainer.mTabstrip.scrollBoxObject;
           for (var i = 0; i < this.childNodes.length; i++) {
-            var curTabBO = this.childNodes[i].tab.boxObject;
+            let curTab = this.childNodes[i].tab;
+            if (!curTab) // "Tab Groups" menuitem and its menuseparator
+              continue;
+            let curTabBO = curTab.boxObject;
+            if (!curTabBO) // "Tabs From Other Computers" menuitem
+              continue;
             if (curTabBO.screenX >= tabstripBO.screenX &&
                 curTabBO.screenX + curTabBO.width <= tabstripBO.screenX + tabstripBO.width)
               this.childNodes[i].setAttribute("tabIsVisible", "true"); 
@@ -3815,7 +3820,7 @@
         // clear out the menu popup and remove the listeners
         for (let i = this.childNodes.length - 1; i > 0; i--) {
           let menuItem = this.childNodes[i];
-          if (!menuItem.hasAttribute("keepme")) {
+          if (menuItem.tab) {
             menuItem.removeEventListener("command", this, false);
             menuItem.tab.mCorrespondingMenuitem = null;
             this.removeChild(menuItem);