Refactor: Decouple failed attachments and the flash messages

Attachment#attach_files will no longer need to return a flash message,
instead it will put unsaved attachments into object#unsaved_attachments
where the calling object can access them.

A utility method #render_attachment_warning_if_needed is included for setting
the standard flash warning.

git-svn-id: svn+ssh://rubyforge.org/var/svn/redmine/trunk@3528 e93f8b46-1217-0410-a6f0-8f06a7374b81

app/controllers/application_controller.rb

@@ -301,4 +301,9 @@ class ApplicationController < ActionController::Base
   def api_request?
     %w(xml json).include? params[:format]
   end
+
+  # Renders a warning flash if obj has unsaved attachments
+  def render_attachment_warning_if_needed(obj)
+    flash[:warning] = l(:warning_attachments_not_saved, obj.unsaved_attachments.size) if obj.unsaved_attachments.present?
+  end
 end