Followup fix to test for bug 586763. a=orange

content/html/content/test/test_bug586763.html

@@ -32,7 +32,7 @@ var tests = [
   ["area", "tabIndex", 0],
   ["button", "tabIndex", 0],
   ["input", "tabIndex", 0],
-  ["object", "tabIndex", 0],
+  ["object", "tabIndex", -1],
   ["select", "tabIndex", 0],
   ["textarea", "tabIndex", 0],
 ];