Fix build.

ICSharpCode.Decompiler/Metadata/DotNetCorePathFinderExtensions.cs

@@ -72,6 +72,8 @@ namespace ICSharpCode.Decompiler.Metadata
 				}
 			}
 
+			if (reader.IsAssembly)
+			{
 				var thisAssemblyName = reader.GetAssemblyDefinition().GetAssemblyName();
 				switch (thisAssemblyName.Name)
 				{
@@ -80,6 +82,7 @@ namespace ICSharpCode.Decompiler.Metadata
 					case "netstandard":
 						return $".NETStandard,Version=v{thisAssemblyName.Version.ToString(2)}";
 				}
+			}
 
 			foreach (var h in reader.AssemblyReferences)
 			{