Fixes dotnet#4647 (dotnet#4673)

Author: gewarren

_zip/missingapi.yml

@@ -29,6 +29,9 @@ references:
   name: PresentationTraceSources.TraceLevel
   fullname: System.Diagnostics.PresentationTraceSources.TraceLevel
   href: https://docs.microsoft.com/previous-versions/bb778381(v=vs.110)
+- uid: System.MonoLimitationAttribute
+  name: MonoLimitationAttribute
+  fullname: System.MonoLimitationAttribute
 - uid: System.MonoNotSupportedAttribute
   name: MonoNotSupportedAttribute
   fullname: System.MonoNotSupportedAttribute