Rails3: use Project.visible.find_by_identifier instead of .find for adding watchers dialog on new issue

On Rails 3.0.12, find_project method returns render_404

git-svn-id: svn+ssh://rubyforge.org/var/svn/redmine/trunk@9464 e93f8b46-1217-0410-a6f0-8f06a7374b81

app/controllers/watchers_controller.rb

@@ -109,7 +109,7 @@ private
       @watched = klass.find(params[:object_id])
       @project = @watched.project
     elsif params[:project_id]
-      @project = Project.visible.find(params[:project_id])
+      @project = Project.visible.find_by_identifier(params[:project_id])
     end
   rescue
     render_404