Only load into buffer if content present

Author: Cheesebaron

src/Microsoft.AspNet.WebApi.MessageHandlers.Compression/ServerCompressionHandler.cs

@@ -101,8 +101,11 @@ protected override async Task<HttpResponseMessage> SendAsync(HttpRequestMessage
 
             try
             {
-                // Buffer content for further processing
-                await response.Content.LoadIntoBufferAsync();
+                if (response.Content != null)
+                    // Buffer content for further processing
+                    await response.Content.LoadIntoBufferAsync();
+                else
+                    process = false;
             }
             catch (Exception ex)
             {
@@ -184,4 +187,4 @@ private async Task DecompressRequest(HttpRequestMessage request)
             }
         }
     }
-}
+}