Made change to set record to nil for relationship screen.

having value in `record` was causing not sending miq_grid_checks along in params when custom button was pressed from a list thru relationships

(cherry picked from commit d8c3cb2)

app/helpers/application_helper/toolbar_builder.rb

@@ -271,7 +271,7 @@ def create_custom_button(input, model, record)
       :enabled   => enabled,
       :klass     => ApplicationHelper::Button::ButtonWithoutRbacCheck,
       :url       => "button",
-      :url_parms => "?id=#{record_id}&button_id=#{button_id}&cls=#{model}&pressed=custom_button&desc=#{button_name}"
+      :url_parms => "?id=LIST&button_id=#{button_id}&cls=#{model}&pressed=custom_button&desc=#{button_name}"
     }
     button[:text] = button_name if input[:text_display]
     button[:onwhen] = '1+' if cb_enabled_for_nested
@@ -330,6 +330,7 @@ def custom_toolbar_class(toolbar_result)
       model = GenericObjectDefinition
       record = GenericObject.find_by(:id => @sb[:rec_id])
     elsif relationship_table_screen?
+      record = nil
       model = custom_button_class_model(@display.camelize.singularize)
     else
       model = @record ? @record.class : model_for_custom_toolbar