title: Async GetAwaiter() throwing an odd exception
body: <p>Below I have pasted some code. On the first line of the body I call an awaitable call <code>Task&lt;IEnumerable&lt;SkuGcn&gt;&gt; GetSkuGcnList();</code> On the last line, in the <code>mapPromise.GetAwaiter()</code> it throws when getting the result with this exception: </p>
  
  <blockquote>
    <p>An exception of type 'System.IO.FileNotFoundException' occurred in System.Private.CoreLib.ni.dll but was not handled in user code</p>
    
    <p>Additional information: Could not load file or assembly 'System.Runtime.Serialization.Xml, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a'. The system cannot find the file specified.</p>
  </blockquote>
  
  <p>I know my service that the <code>GetSkuGcnList()</code> call is calling to, is being called, because I can set a break point and I break at it when the call is made.  Then the service seems to return.</p>
  
  <p>This code worked just fine with ASP.NET 5 RC1 but now not so good in ASP.Net Core 1.0 Release.</p>
  
  <p>Any help will be greatly appreciated!</p>
  
  <pre><code>        public ProductItemsCacheStore(IItemsProductCacheRepository itemsRepo, IProductAvailabilityPricing proxyGoliathApi,
          IProductItemListRepo itemsListsRepo, IItemPricesCacheRepo itemPricesRepo)
          {
              var mapPromise = proxyGoliathApi.GetSkuGcnList();
              _items = itemsRepo.GetAllProductOrderListForCache();
              _itemsLists = itemsListsRepo.GetItemListsForCache();
              _priceZones = itemPricesRepo.GetAllPriceZonesAndItemPrices();
              MergeProductsWithGcn(_items, mapPromise.GetAwaiter().GetResult());
          }
  </code></pre>
  
  <p>My project.json looks like this:</p>
  
  <pre><code>{
    "version": "1.0.0-alpha.1",
    "description": "AvailabilityPricingClient Class Library",
    "authors": [ "irving.lennert" ],
    "packOptions": {
      "tags": [ "" ],
      "projectUrl": "",
      "licenseUrl": ""
    },
  
    "tooling": {
      "defaultNamespace": "AvailabilityPricingClient"
    },
  
    "dependencies": {
      "Microsoft.NETCore.App": {
        "version": "1.0.0",
        "type": "platform"
      },
      "Microsoft.AspNetCore.Server.IISIntegration": "1.0.0",
      "Microsoft.AspNetCore.Server.Kestrel": "1.0.0",
      "Microsoft.Extensions.Configuration.Json": "1.0.0",
      "Microsoft.Extensions.Logging": "1.0.0",
      "Microsoft.Extensions.Logging.Console": "1.0.0",
      "Microsoft.Extensions.Logging.Debug": "1.0.0",
      "Microsoft.AspNet.WebApi.Client": "5.2.3"
    },
  
    "frameworks": {
      "netcoreapp1.0": {
        "imports": [
          "dotnet5.6",
          "portable-net45+win8"
        ]
      }
    }
  }
  </code></pre>
  
  <p>The implementation of <code>GetSkuGcnList()</code> is this:</p>
  
  <pre><code>    public async Task&lt;IEnumerable&lt;SkuGcn&gt;&gt; GetSkuGcnList()
      {
          HttpResponseMessage response = _client.GetAsync("/api/skuGcnList").Result;
  
          if (response.IsSuccessStatusCode)
          {
              var skuGcns = await response.Content.ReadAsAsync&lt;IEnumerable&lt;SkuGcn&gt;&gt;();
              return skuGcns;
          }
  
          return null;
      }
  </code></pre>