Add instance option to append a CSS class for rows

app/views/rails_admin/main/index.html.haml

@@ -90,7 +90,7 @@
           %th.last.shrink
       %tbody
         - @objects.each do |object|
-          %tr{class: "#{@abstract_model.param_key}_row"}
+          %tr{class: "#{@abstract_model.param_key}_row #{@model_config.list.with(object: object).row_css_class}"}
             %td
               = check_box_tag "bulk_ids[]", object.id, false
             - if @other_left_link ||= other_left && index_path(params.except('set').merge(params[:set].to_i != 1 ? {set: (params[:set].to_i - 1)} : {}))

lib/rails_admin/config/sections/list.rb

@@ -25,6 +25,10 @@ class List < RailsAdmin::Config::Sections::Base
         register_instance_option :scopes do
           []
         end
+
+        register_instance_option :row_css_class do
+          ''
+        end
       end
     end
   end

spec/integration/basic/list/rails_admin_basic_list_spec.rb

@@ -564,4 +564,27 @@
       end
     end
   end
+
+  describe 'Row CSS class' do
+    before do
+      RailsAdmin.config do |config|
+        config.model Team do
+          list do
+            row_css_class { 'my_class' }
+          end
+        end
+      end
+      @teams = [
+        FactoryGirl.create(:team, color: 'red'),
+        FactoryGirl.create(:team, color: 'red'),
+        FactoryGirl.create(:team, color: 'white'),
+        FactoryGirl.create(:team, color: 'black'),
+      ]
+    end
+
+    it 'appends the CSS class to the model row class' do
+      visit index_path(model_name: 'team')
+      expect(page).to have_css('tr.team_row.my_class')
+    end
+  end
 end