ActionMailer should not depend on ActionDispatch

actionmailer/lib/action_mailer.rb

@@ -26,7 +26,6 @@ $:.unshift(actionpack_path) if File.directory?(actionpack_path) && !$:.include?(
 
 require 'abstract_controller'
 require 'action_view'
-require 'action_dispatch'
 
 # Common Active Support usage in Action Mailer
 require 'active_support/core_ext/class'

actionmailer/lib/action_mailer/base.rb

@@ -340,7 +340,6 @@ module ActionMailer #:nodoc:
     include AbstractController::Helpers
     include AbstractController::Translation
     include AbstractController::AssetPaths
-    include AbstractController::UrlFor
 
     cattr_reader :protected_instance_variables
     @@protected_instance_variables = []
@@ -364,7 +363,7 @@ module ActionMailer #:nodoc:
     class << self
       def inherited(klass)
         super(klass)
-        klass.class_eval { @action_methods = nil }
+        klass.clear_action_methods!
       end
 
       def mailer_name

actionmailer/lib/action_mailer/railtie.rb

@@ -19,6 +19,7 @@ module ActionMailer
       options.stylesheets_dir ||= paths.public.stylesheets.to_a.first
 
       ActiveSupport.on_load(:action_mailer) do
+        include AbstractController::UrlFor
         extend ::AbstractController::Railties::RoutesHelpers.with(app.routes)
         include app.routes.mounted_helpers(:app)
         options.each { |k,v| send("#{k}=", v) }