When a search result doesn't exist, it is not displayed

- Might occur when a deleted content is searched before the index is updated (short time), eventually when the search is triggered on another server of a farm

--HG--
branch : dev

src/Orchard.Web/Modules/Orchard.Search/Controllers/SearchController.cs

@@ -5,6 +5,7 @@ using Orchard.Search.Services;
 using Orchard.Search.ViewModels;
 using Orchard.Settings;
 using Orchard.Search.Models;
+using System.Linq;
 using System;
 
 namespace Orchard.Search.Controllers {

src/Orchard.Web/Modules/Orchard.Search/Views/Search/Index.ascx

@@ -12,6 +12,6 @@ if (!string.IsNullOrWhiteSpace(Model.Query)) {
     }
 }
 if (Model.PageOfResults != null && Model.PageOfResults.Count() > 0) { %>
-<%=Html.UnorderedList(Model.PageOfResults, (r, i) => Html.DisplayForItem(r.Content) , "search-results contentItems") %>
+<%=Html.UnorderedList(Model.PageOfResults.Where(hit => hit.Content != null), (r, i) => Html.DisplayForItem(r.Content), "search-results contentItems")%>
 <%=Html.Pager(Model.PageOfResults, Model.PageOfResults.PageNumber, Model.DefaultPageSize, new {q = Model.Query}) %><%
 } %>

src/Orchard/ContentManagement/DefaultContentManager.cs

@@ -385,6 +385,9 @@ namespace Orchard.ContentManagement {
         }
 
         public ContentItemViewModel<TContentPart> BuildDisplayModel<TContentPart>(TContentPart content, string displayType) where TContentPart : IContent {
+            if (content == null)
+                return null;
+
             var displayModel = new ContentItemViewModel<TContentPart>(content);
             var context = new BuildDisplayModelContext(displayModel, displayType);
             foreach (var handler in Handlers) {