Apparently we can't handle "thin" here yet.

layout/style/test/test_value_computation.html

@@ -107,7 +107,10 @@ var gBadComputed = {
   "clip": [ "rect(auto,auto,auto,auto)" ],
 
   // No idea what's happening for these two either
+  "border-top": [ "thin" ],
+  "border-right": [ "thin" ],
   "border-bottom": [ "thin" ],
+  "border-left": [ "thin" ],
   "outline-width": [ "3px" ],
 
   // 'normal' should compute to 0