Modified InheritedAttributes to only display inherited attributes

Previously, a bug was introduced in which inherited attributes were set to the _current_ topic's attributes—which may be inherited, but may not be. It's not entirely clear _why_ that change was made, but it causes confusion because the inherited value is used as the placeholder on attribute fields. As such, if you remove an existing value from a field, that value appears to reappear as theplaceholder text.

We can fix this by simply going back to using the `DerivedTopic` version, which is how we handled this in the previous version of the editor. We'll need to be on the lookout for off-target impacts in case there was a good reason to introduce this, though. If so, we'll need to find a workaround, and carefully comment it for future versions of me.

Author: JeremyCaney

OnTopic.Editor.AspNetCore/Controllers/EditorController.cs

@@ -176,7 +176,10 @@ bool isModal
         }
 
         //Set inherited attribute value, if available
-        topicViewModel.InheritedAttributes.Add(attribute.Key, isNew? null : CurrentTopic.Attributes.GetValue(attribute.Key));
+        topicViewModel.InheritedAttributes.Add(
+          attribute.Key,
+          isNew? null : CurrentTopic.DerivedTopic?.Attributes.GetValue(attribute.Key)
+        );
 
       }
 

OnTopic.Editor.Models/AttributeViewModel.cs

@@ -74,10 +74,6 @@ AttributeDescriptorTopicViewModel attributeDescriptor
     /// <summary>
     ///   Provides the inherited value, as defined on either parent or derived topics.
     /// </summary>
-    /// <remarks>
-    ///   If the <see cref="Value"/> is set, then the <see cref="InhertedValue"/> will always be equal to the
-    ///   <see cref="Value"/>.
-    /// </remarks>
     public virtual string InheritedValue { get; set; }
 
   } // Class