push param encoding in to the utils module

we'll refactor deep munge mostly out of existence shortly

actionpack/lib/action_dispatch/http/parameters.rb

@@ -37,20 +37,7 @@ module ActionDispatch
       # Convert nested Hash to HashWithIndifferentAccess.
       #
       def normalize_encode_params(params)
-        case params
+        ActionDispatch::Request::Utils.normalize_encode_params params
-        when Array
-          params.map! { |el| normalize_encode_params(el) }
-        when Hash
-          if params.has_key?(:tempfile)
-            UploadedFile.new(params)
-          else
-            params.each_with_object({}) do |(key, val), new_hash|
-              new_hash[key] = normalize_encode_params(val)
-            end.with_indifferent_access
-          end
-        else
-          params
-        end
       end
     end
   end

actionpack/lib/action_dispatch/request/utils.rb

@@ -5,6 +5,35 @@ module ActionDispatch
       mattr_accessor :perform_deep_munge
       self.perform_deep_munge = true
 
+      def self.normalize_encode_params(params)
+        ParamEncoder.normalize_encode_params params
+      end
+
+      class ParamEncoder
+        # Convert nested Hash to HashWithIndifferentAccess.
+        #
+        def self.normalize_encode_params(params)
+          case params
+          when Array
+            handle_array params
+          when Hash
+            if params.has_key?(:tempfile)
+              ActionDispatch::Http::UploadedFile.new(params)
+            else
+              params.each_with_object({}) do |(key, val), new_hash|
+                new_hash[key] = normalize_encode_params(val)
+              end.with_indifferent_access
+            end
+          else
+            params
+          end
+        end
+
+        def self.handle_array(params)
+          params.map! { |el| normalize_encode_params(el) }
+        end
+      end
+
       class << self
         # Remove nils from the params hash
         def deep_munge(hash)