- PERF: Fix the role based auth service to not recalculate permission checks again and again.

- Adding some comments to the authorization event handler interface.

--HG--
branch : dev

src/Orchard.Web/Modules/Orchard.Roles/Services/RolesBasedAuthorizationService.cs

@@ -84,6 +84,8 @@ namespace Orchard.Roles.Services {
 
                 context.Adjusted = false;
                 _authorizationServiceEventHandler.Adjust(context);
+                if (!context.Adjusted)
+                    break;
             }
 
             _authorizationServiceEventHandler.Complete(context);

src/Orchard/Security/IAuthorizationServiceEventHandler.cs

@@ -13,7 +13,12 @@ namespace Orchard.Security {
         public Permission Permission { get; set; }
         public IUser User { get; set; }
         public IContent Content { get; set; }
+        
+        // true if the permission has been granted to the user.
         public bool Granted { get; set; }
+        
+        // if context.Permission was modified during an Adjust(context) in an event handler, Adjusted should be set to true.
+        // It means that the permission check will be done again by the framework.
         public bool Adjusted { get; set; }
     }
 }