Add a test case for a desktop app using Command.CreateDotnet, expecting to fail

TestAssets/DesktopTestProjects/DesktopAppWhichCallsDotnet/Program.cs

@@ -0,0 +1,21 @@
+using System;
+using Microsoft.DotNet.Cli.Utils;
+using System.IO;
+
+namespace DesktopAppWhichCallsDotnet
+{
+    public class Program
+    {
+        public static int Main(string[] args)
+        {
+            var projectPath = args[0];
+            
+            return Command.CreateDotNet("build", new string[] {})
+                .WorkingDirectory(Path.GetDirectoryName(projectPath))
+                .ForwardStdErr()
+                .ForwardStdOut()
+                .Execute()
+                .ExitCode;
+        }
+    }
+}

TestAssets/DesktopTestProjects/DesktopAppWhichCallsDotnet/project.json

@@ -0,0 +1,12 @@
+{
+  "version": "1.0.0-*",
+  "dependencies": {
+    "Microsoft.DotNet.Cli.Utils": "1.0.0-*"
+  },
+  "compilationOptions": {
+    "emitEntryPoint": true
+  },
+  "frameworks": {
+    "net451": {}
+  }
+}