Fix mobile registration layout after failed registration

closes #6677

Changelog.md

@@ -9,6 +9,7 @@
 * Fix plural rules handling more than wanted as "one" [#6630](https://github.com/diaspora/diaspora/pull/6630)
 * Fix `suppress_annoying_errors` eating too much errors [#6653](https://github.com/diaspora/diaspora/pull/6653)
 * Ensure the rubyzip gem is properly loaded [#6659](https://github.com/diaspora/diaspora/pull/6659)
+* Fix mobile registration layout after failed registration [#6677](https://github.com/diaspora/diaspora/pull/6677)
 
 ## Features
 * Keyboard shortcuts now do work on profile pages as well [#6647](https://github.com/diaspora/diaspora/pull/6647/files)

app/controllers/registrations_controller.rb

@@ -22,7 +22,7 @@ class RegistrationsController < Devise::RegistrationsController
 
       flash.now[:error] = @user.errors.full_messages.join(" - ")
       logger.info "event=registration status=failure errors='#{@user.errors.full_messages.join(', ')}'"
-      render :action => 'new', :layout => 'with_header'
+      render action: "new", layout: request.format == :mobile ? "application" : "with_header"
     end
   end