speeding up flattened version of OrderedHash.[]

activesupport/lib/active_support/ordered_hash.rb

@@ -64,9 +64,8 @@ def self.[](*args)
           raise ArgumentError.new("odd number of arguments for Hash")
         end
 
-        args.each_with_index do |val, ind|
-          next if (ind % 2 != 0)
-          ordered_hash[val] = args[ind + 1]
+        0.step(args.length, 2) do |ind|
+          ordered_hash[args[ind]] = args[ind + 1]
         end
 
         ordered_hash