Remove symbolized_path_parameters.

This pull request is a continuation of https://github.com/rails/rails/commit/925bd975 and https://github.com/rails/rails/commit/8d8ebe3d.

actionpack/lib/action_controller/test_case.rb

@@ -233,7 +233,6 @@ def recycle!
       @formats = nil
       @env.delete_if { |k, v| k =~ /^(action_dispatch|rack)\.request/ }
       @env.delete_if { |k, v| k =~ /^action_dispatch\.rescue/ }
-      @symbolized_path_params = nil
       @method = @request_method = nil
       @fullpath = @ip = @remote_ip = @protocol = nil
       @env['action_dispatch.request.query_parameters'] = {}

actionpack/lib/action_dispatch/http/parameters.rb

@@ -1,5 +1,6 @@
 require 'active_support/core_ext/hash/keys'
 require 'active_support/core_ext/hash/indifferent_access'
+require 'active_support/deprecation'
 
 module ActionDispatch
   module Http
@@ -24,8 +25,10 @@ def path_parameters=(parameters) #:nodoc:
         @env[PARAMETERS_KEY] = parameters
       end
 
-      # The same as <tt>path_parameters</tt> with explicitly symbolized keys.
       def symbolized_path_parameters
+        ActiveSupport::Deprecation.warn(
+          "`symbolized_path_parameters` is deprecated. Please use `path_parameters`"
+        )
         path_parameters
       end
 
@@ -33,8 +36,6 @@ def symbolized_path_parameters
       # Returned hash keys are strings:
       #
       #   {'action' => 'my_action', 'controller' => 'my_controller'}
-      #
-      # See <tt>symbolized_path_parameters</tt> for symbolized keys.
       def path_parameters
         @env[PARAMETERS_KEY] ||= {}
       end

actionpack/lib/action_dispatch/testing/test_request.rb

@@ -39,7 +39,7 @@ def path=(path)
     end
 
     def action=(action_name)
-      path_parameters["action"] = action_name.to_s
+      path_parameters[:action] = action_name.to_s
     end
 
     def if_modified_since=(last_modified)

actionpack/test/controller/test_case_test.rb

@@ -737,12 +737,12 @@ def test_filtered_parameters_reset_between_requests
     assert_equal "baz", @request.filtered_parameters[:foo]
   end
 
-  def test_symbolized_path_params_reset_after_request
+  def test_path_params_reset_after_request
     get :test_params, :id => "foo"
-    assert_equal "foo", @request.symbolized_path_parameters[:id]
+    assert_equal "foo", @request.path_parameters[:id]
     @request.recycle!
     get :test_params
-    assert_nil @request.symbolized_path_parameters[:id]
+    assert_nil @request.path_parameters[:id]
   end
 
   def test_request_protocol_is_reset_after_request

actionpack/test/dispatch/routing_test.rb

@@ -2831,7 +2831,7 @@ def test_redirect_https
     end
   end
 
-  def test_symbolized_path_parameters_is_not_stale
+  def test_path_parameters_is_not_stale
     draw do
       scope '/countries/:country', :constraints => lambda { |params, req| %w(all France).include?(params[:country]) } do
         get '/',       :to => 'countries#index'
@@ -3148,7 +3148,7 @@ def test_multiple_positional_args_with_the_same_name
 
     get '/downloads/1/1.tar'
     assert_equal 'downloads#show', @response.body
-    assert_equal expected_params, @request.symbolized_path_parameters
+    assert_equal expected_params, @request.path_parameters
     assert_equal '/downloads/1/1.tar', download_path('1')
     assert_equal '/downloads/1/1.tar', download_path('1', '1')
   end