don't pass notification email into to the default cause it freezes in a potentially incorrect value

app/mailers/invite_mailer.rb

@@ -2,7 +2,6 @@ require_dependency 'email_builder'
 
 class InviteMailer < ActionMailer::Base
   include EmailBuilder
-  default from: SiteSetting.notification_email
 
   def send_invite(invite)
 

app/mailers/test_mailer.rb

@@ -3,8 +3,6 @@ require_dependency 'email_builder'
 class TestMailer < ActionMailer::Base
   include EmailBuilder
 
-  default from: SiteSetting.notification_email
-
   def send_test(to_address)
     build_email to_address, 'test_mailer'
   end

app/mailers/user_notifications.rb

@@ -4,8 +4,6 @@ require_dependency 'email_builder'
 class UserNotifications < ActionMailer::Base
   include EmailBuilder
 
-  default from: SiteSetting.notification_email
-
   def signup(user, opts={})
     build_email(user.email, "user_notifications.signup", email_token: opts[:email_token])
   end

lib/email_builder.rb

@@ -19,8 +19,7 @@ module EmailBuilder
       subject: I18n.t("#{email_key}.subject_template", params),
       body: body
     }
-    mail_args[:from] = params[:from] if params[:from].present?
-
+    mail_args[:from] = params[:from] || SiteSetting.notification_email
     mail(mail_args)
   end