#366 Rewind the request buffer after parsing the form.

src/Microsoft.AspNet.Http/Features/FormFeature.cs

@@ -152,6 +152,9 @@ namespace Microsoft.AspNet.Http.Features.Internal
                 }
             }
 
+            // Rewind so later readers don't have to.
+            _request.Body.Seek(0, SeekOrigin.Begin);
+
             Form = new FormCollection(formFields, files);
             return Form;
         }

test/Microsoft.AspNet.Http.Tests/FormFeatureTests.cs

@@ -32,6 +32,8 @@ namespace Microsoft.AspNet.Http.Features.Internal
             // Assert
             Assert.Equal("bar", formCollection["foo"]);
             Assert.Equal("2", formCollection["baz"]);
+            Assert.Equal(0, context.Request.Body.Position);
+            Assert.True(context.Request.Body.CanSeek);
 
             // Cached
             formFeature = context.Features.Get<IFormFeature>();