Fix build break

- no need to call (`internal`) `html.GenerateId()` method since it matches `html.Id()` exactly
- no need for `.ToString()` with either method since they return `string` now

src/MusicStore.Spa/Helpers/AngularExtensions.cs

@@ -239,7 +239,7 @@ namespace Microsoft.AspNet.Mvc.Rendering
             var displayFieldNameParts = displayFieldName.Split('.');
             displayFieldName = displayFieldNameParts[displayFieldNameParts.Length - 1];
             
-            tag.Attributes["id"] = helper.GetFullHtmlFieldId(propertyExpressionText).ToString();
+            tag.Attributes["id"] = html.Id(propertyExpressionText);
             tag.Attributes["name"] = valueFieldName;
             tag.Attributes["ng-model"] = valueFieldName;
 

src/MusicStore.Spa/Helpers/AngularHtmlHelper'T.cs

@@ -26,10 +26,5 @@ namespace Microsoft.AspNet.Mvc.Rendering
         {
             return GetClientValidationRules(metadata, name);
         }
-
-        public HtmlString GetFullHtmlFieldId(string expression)
-        {
-            return GenerateId(expression);
-        }
     }
 }