Made the post_format work with content-type

git-svn-id: http://svn-commit.rubyonrails.org/rails/trunk@1337 5ecf4fe2-1ee6-0310-87b1-e25e094e27de

actionpack/lib/action_controller/request.rb

@@ -35,7 +35,7 @@ def post_format
       if env['HTTP_X_POST_DATA_FORMAT']
         env['HTTP_X_POST_DATA_FORMAT'].downcase.intern
       else
-        case env['HTTP_CONTENT_TYPE']
+        case env['CONTENT_TYPE']
           when 'application/xml', 'text/xml'
             :xml
           when 'application/x-yaml', 'text/x-yaml'