Merge pull request #62412 from bhcleek/go1.10

Automatic merge from submit-queue. If you want to cherry-pick this change to another branch, please follow the instructions <a href="https://github.com/kubernetes/community/blob/master/contributors/devel/cherry-picks.md">here</a>.

generated code should pass go vet for go1.10

**What this PR does / why we need it**:

Update code generator and the code it generates to pass `go vet`.

go1.10 runs `go vet` whenever `go test` is run. Because of this, generated code for CRDs needs to pass `go vet`.

**Release note**:

```release-note
Code generated for CRDs now passes `go vet`.
```

Kubernetes-commit: 5dde701b876d1d0915314c3ed146e986c4327f7e

vendor/k8s.io/apimachinery/pkg/apis/meta/v1/unstructured/helpers.go

@@ -436,6 +436,21 @@ func (s unstructuredJSONScheme) decodeToList(data []byte, list *UnstructuredList
 	return nil
 }
 
+type JSONFallbackEncoder struct {
+	runtime.Encoder
+}
+
+func (c JSONFallbackEncoder) Encode(obj runtime.Object, w io.Writer) error {
+	err := c.Encoder.Encode(obj, w)
+	if runtime.IsNotRegisteredError(err) {
+		switch obj.(type) {
+		case *Unstructured, *UnstructuredList:
+			return UnstructuredJSONScheme.Encode(obj, w)
+		}
+	}
+	return err
+}
+
 // UnstructuredObjectConverter is an ObjectConverter for use with
 // Unstructured objects. Since it has no schema or type information,
 // it will only succeed for no-op conversions. This is provided as a