Use require_dependency in generated controllers

Using require in development mode will prevent required files from
reloading, even if they're changed. In order to keep namespaced
application_controller reloadable, we need to use require_dependency
instead of require.

railties/lib/rails/generators/rails/controller/templates/controller.rb

@@ -1,5 +1,5 @@
 <% if  namespaced? -%>
-require "<%= namespaced_file_path %>/application_controller"
+require_dependency "<%= namespaced_file_path %>/application_controller"
 <% end  -%>
 
 <% module_namespacing  do -%>

railties/lib/rails/generators/rails/scaffold_controller/templates/controller.rb

@@ -1,5 +1,5 @@
 <% if  namespaced? -%>
-require "<%= namespaced_file_path %>/application_controller"
+require_dependency "<%= namespaced_file_path %>/application_controller"
 <% end  -%>
 
 <% module_namespacing  do -%>

railties/test/generators/namespaced_generators_test.rb

@@ -21,7 +21,7 @@ class NamespacedControllerGeneratorTest < NamespacedGeneratorTestCase
   def test_namespaced_controller_skeleton_is_created
     run_generator
     assert_file "app/controllers/test_app/account_controller.rb",
-                /require "test_app\/application_controller"/,
+                /require_dependency "test_app\/application_controller"/,
                 /module TestApp/,
                 /  class AccountController < ApplicationController/
 
@@ -234,7 +234,7 @@ class NamespacedScaffoldGeneratorTest < NamespacedGeneratorTestCase
 
     # Controller
     assert_file "app/controllers/test_app/product_lines_controller.rb",
-                /require "test_app\/application_controller"/,
+                /require_dependency "test_app\/application_controller"/,
                 /module TestApp/,
                 /class ProductLinesController < ApplicationController/