New view engines cache implementation for tenant compatibility with themes

--HG--
branch : dev

src/Orchard/Mvc/ViewEngines/ThemeViewLocationCache.cs

@@ -0,0 +1,38 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Web.Mvc;
+using System.Web.Caching;
+using System.Web;
+using System.Web.Hosting;
+
+namespace Orchard.Mvc.ViewEngines {
+    public class ThemeViewLocationCache : IViewLocationCache {
+        private readonly string _requestTheme;
+
+        public ThemeViewLocationCache(string requestTheme) {
+            _requestTheme = requestTheme;
+        }
+
+        private string AlterKey(string key) {
+            return key + ":" + _requestTheme;
+        }
+
+        public string GetViewLocation(HttpContextBase httpContext, string key) {
+            if (httpContext == null) {
+                throw new ArgumentNullException("httpContext");
+            }
+
+            return (string)httpContext.Cache[AlterKey(key)];
+        }
+
+        public void InsertViewLocation(HttpContextBase httpContext, string key, string virtualPath) {
+            if (httpContext == null) {
+                throw new ArgumentNullException("httpContext");
+            }
+
+            httpContext.Cache.Insert(AlterKey(key), virtualPath, new CacheDependency(HostingEnvironment.MapPath("~/Themes")), Cache.NoAbsoluteExpiration, TimeSpan);
+        }
+    }
+}

src/Orchard/Mvc/ViewEngines/WebFormsViewEngineProvider.cs

@@ -31,6 +31,8 @@ namespace Orchard.Mvc.ViewEngines {
                 AreaPartialViewLocationFormats = DisabledFormats,
             };
 
+            viewEngine.ViewLocationCache = new ThemeViewLocationCache(parameters.VirtualPath);
+
             // enable /Views/{partialName}
             // enable /Views/"DisplayTemplates/"+{templateName}
             // enable /Views/"EditorTemplates/+{templateName}

src/Orchard/Orchard.Framework.csproj

@@ -235,6 +235,7 @@
     <Compile Include="Mvc\Routes\UrlPrefix.cs" />
     <Compile Include="Mvc\Routes\UrlPrefixAdjustedHttpContext.cs" />
     <Compile Include="Mvc\Routes\ShellRoute.cs" />
+    <Compile Include="Mvc\ViewEngines\ThemeViewLocationCache.cs" />
     <Compile Include="Mvc\ViewModels\AdaptedViewModel.cs" />
     <Compile Include="Mvc\ViewUserControl.cs">
       <SubType>ASPXCodeBehind</SubType>