[MIGRATION] Unable to build Xamarin Forms App after project migration

[kvbhat]

Steps to reproduce

Reduced test case-

Program.cs:

using System;

namespace ConsoleApplication
{
    public class Program
    {
        public static void Main(string[] args)
        {
            Console.WriteLine("Hello World!");
        }
    }
}

project.json:

{
  "version": "1.0.0-*",
  "buildOptions": {
    "debugType": "portable",
    "platform": "AnyCPU",
    "preserveCompilationContext": true
  },
  "dependencies": { "Microsoft.NETCore.App": {
      "version": "1.0.0"
    },
    "Xamarin.Forms": "2.3.3.163-pre3"
  },
  "runtimes": {
    "win": {},
    "linux": {}
  },
 "frameworks": {
    "netcoreapp1.0": {
      "imports": [
        "portable-net45+wp80+win81+wpa81",
        "netstandard1.6"
      ]
    }
  }
}

run dotnet migrate
run dotnet restore
run dotnet build

Expected behavior

Build should be successful.
With old dotnet build used to succeed but after migration to .csproj build fails when we have a Xamarin.Forms dependency.

Actual behavior

Build Error Reported-

/home/karthik/.nuget/packages/xamarin.forms/2.3.3.163-pre3/build/portable-win+net45+wp80+win81+wpa81+MonoAndroid10+Xamarin.iOS10+xamarinmac20/Xamarin.Forms.targets(40,3): error MSB4062: The "Xamarin.Forms.Build.Tasks.FixedCreateCSharpManifestResourceName" task could not be loaded from the assembly /home/karthik/.nuget/packages/xamarin.forms/2.3.3.163-pre3/build/portable-win+net45+wp80+win81+wpa81+MonoAndroid10+Xamarin.iOS10+xamarinmac20/Xamarin.Forms.Build.Tasks.dll. Could not load file or assembly 'Microsoft.Build.Tasks.v4.0, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a'. The system cannot find the file specified. [/home/karthik/Desktop/dotnet-proj/sample/sample.csproj]
/home/karthik/.nuget/packages/xamarin.forms/2.3.3.163-pre3/build/portable-win+net45+wp80+win81+wpa81+MonoAndroid10+Xamarin.iOS10+xamarinmac20/Xamarin.Forms.targets(40,3): error MSB4062: Confirm that the declaration is correct, that the assembly and all its dependencies are available, and that the task contains a public class that implements Microsoft.Build.Framework.ITask. [/home/karthik/Desktop/dotnet-proj/sample/sample.csproj]

Environment data

dotnet --info output:

.NET Command Line Tools (2.0.0-preview1-005448)

Product Information:
Version: 2.0.0-preview1-005448
Commit SHA-1 hash: f8c3c4a

Runtime Environment:
OS Name: ubuntu
OS Version: 14.04
OS Platform: Linux
RID: ubuntu.14.04-x64
Base Path: /home/karthik/Desktop/dotnet-dev-ubuntu-x64.latest/sdk/2.0.0-preview1-005448/

[dasMulli]

(Related discussions happened in https://github.com/dotnet/cli/issues/5457)

[livarcocc]

This CLI right now support .NET Core and a subset of full framework projects. We don't currently have a timeline for supporting Xamarim on the CLI, though it is definitely something we would like to do. However, I will close this issue for now.