Merge branch temp8 into temp8-U4-11227

src/Umbraco.Core/Models/MediaType.cs

@@ -48,7 +48,7 @@ namespace Umbraco.Core.Models
         /// Creates a deep clone of the current entity with its identity/alias and it's property identities reset
         /// </summary>
         /// <returns></returns>
-        public IMediaType DeepCloneWithResetIdentities(string alias)
+        public new IMediaType DeepCloneWithResetIdentities(string alias)
         {
             var clone = (MediaType)DeepClone();
             clone.Alias = alias;

src/Umbraco.Core/Models/PropertyGroupCollection.cs

@@ -67,8 +67,10 @@ namespace Umbraco.Core.Models
 
         internal new void Add(PropertyGroup item)
         {
-            using (new WriteLock(_addLocker))
+            try
             {
+                _addLocker.EnterWriteLock();
+
                 //Note this is done to ensure existig groups can be renamed
                 if (item.HasIdentity && item.Id > 0)
                 {
@@ -102,6 +104,11 @@ namespace Umbraco.Core.Models
 
                 OnCollectionChanged(new NotifyCollectionChangedEventArgs(NotifyCollectionChangedAction.Add, item));
             }
+            finally
+            {
+                if (_addLocker.IsWriteLockHeld)
+                    _addLocker.ExitWriteLock();
+            }
         }
 
         /// <summary>

src/Umbraco.Core/Models/PropertyTypeCollection.cs

@@ -80,8 +80,9 @@ namespace Umbraco.Core.Models
             item.IsPublishing = IsPublishing;
 
             // fixme redo this entirely!!!
-            using (new WriteLock(_addLocker))
+            try
             {
+                _addLocker.EnterWriteLock();
                 var key = GetKeyForItem(item);
                 if (key != null)
                 {
@@ -105,6 +106,11 @@ namespace Umbraco.Core.Models
 
                 OnCollectionChanged(new NotifyCollectionChangedEventArgs(NotifyCollectionChangedAction.Add, item));
             }
+            finally
+            {
+                if (_addLocker.IsWriteLockHeld)
+                    _addLocker.ExitWriteLock();
+            }
         }
 
         /// <summary>