Revert "Merge pull request #16966 from why-el/symbolize-path-params"

This reverts commit 9d05d6de, reversing
changes made to 0863c924.

The change in the behaviour reported at #16958 doesn't exist since 4.0
and 4.1 works in the same way

actionpack/lib/action_dispatch/routing/route_set.rb

@@ -287,7 +287,6 @@ def handle_positional_args(controller_options, inner_options, args, result, path
               }
             end
 
-            inner_options.symbolize_keys!
             result.merge!(inner_options)
           end
         end

actionpack/test/dispatch/routing/route_set_test.rb

@@ -80,14 +80,6 @@ def call(env)
         assert_equal '/foo/1/bar/2', url_helpers.foo_bar_path(2, foo_id: 1)
       end
 
-      test "stringified controller and action keys are properly symbolized" do
-        draw do
-          root 'foo#bar'
-        end
-
-        assert_equal '/', url_helpers.root_path('controller' => 'foo', 'action' => 'bar')
-      end
-
       private
         def draw(&block)
           @set.draw(&block)