Fix 202792 - remove startup JS warnings, patch by holyspirit@hkpeople.net and brantgurganus2001@cherokeescouting.org

browser/base/content/tabbrowser.xml

@@ -759,9 +759,6 @@
             // Now select the new tab before nuking the old one.
             var currentIndex = this.mPanelContainer.selectedIndex;
 
-            // Now select the new tab before nuking the old one.
-            var currentIndex = this.mPanelContainer.selectedIndex;
-            
             var newIndex = -1;
             if (currentIndex > index)
               newIndex = currentIndex-1;