unify register.go formats:

networking/v1/register.go
staging/src/k8s.io/kube-apiextensions-server/pkg/apis/apiextensions/v1alpha1/register.go
staging/src/k8s.io/metrics/pkg/apis/custom_metrics/v1alpha1/register.go
staging/src/k8s.io/metrics/pkg/apis/metrics/v1alpha1 register.go

pkg/apis/networking/v1/register.go

@@ -34,10 +34,20 @@ func Resource(resource string) schema.GroupResource {
 }
 
 var (
-	SchemeBuilder = runtime.NewSchemeBuilder(addKnownTypes, addDefaultingFuncs, addConversionFuncs)
-	AddToScheme   = SchemeBuilder.AddToScheme
+	// TODO: move SchemeBuilder with zz_generated.deepcopy.go to k8s.io/api.
+	// localSchemeBuilder and AddToScheme will stay in k8s.io/kubernetes.
+	SchemeBuilder      runtime.SchemeBuilder
+	localSchemeBuilder = &SchemeBuilder
+	AddToScheme        = localSchemeBuilder.AddToScheme
 )
 
+func init() {
+	// We only register manually written functions here. The registration of the
+	// generated functions takes place in the generated files. The separation
+	// makes the code compile even when the generated files are missing.
+	localSchemeBuilder.Register(addKnownTypes, addDefaultingFuncs, addConversionFuncs)
+}
+
 // Adds the list of known types to api.Scheme.
 func addKnownTypes(scheme *runtime.Scheme) error {
 	scheme.AddKnownTypes(SchemeGroupVersion,

staging/src/k8s.io/apiextensions-apiserver/pkg/apis/apiextensions/v1beta1/register.go

@@ -38,8 +38,9 @@ func Resource(resource string) schema.GroupResource {
 }
 
 var (
-	SchemeBuilder = runtime.NewSchemeBuilder(addKnownTypes, addDefaultingFuncs)
-	AddToScheme   = SchemeBuilder.AddToScheme
+	SchemeBuilder      = runtime.NewSchemeBuilder(addKnownTypes, addDefaultingFuncs)
+	localSchemeBuilder = &SchemeBuilder
+	AddToScheme        = localSchemeBuilder.AddToScheme
 )
 
 // Adds the list of known types to api.Scheme.

staging/src/k8s.io/metrics/pkg/apis/custom_metrics/v1alpha1/register.go

@@ -34,8 +34,9 @@ func Resource(resource string) schema.GroupResource {
 }
 
 var (
-	SchemeBuilder = runtime.NewSchemeBuilder(addKnownTypes)
-	AddToScheme   = SchemeBuilder.AddToScheme
+	SchemeBuilder      = runtime.NewSchemeBuilder(addKnownTypes)
+	localSchemeBuilder = &SchemeBuilder
+	AddToScheme        = localSchemeBuilder.AddToScheme
 )
 
 func addKnownTypes(scheme *runtime.Scheme) error {

staging/src/k8s.io/metrics/pkg/apis/metrics/v1alpha1/register.go

@@ -34,8 +34,9 @@ func Resource(resource string) schema.GroupResource {
 }
 
 var (
-	SchemeBuilder = runtime.NewSchemeBuilder(addKnownTypes)
-	AddToScheme   = SchemeBuilder.AddToScheme
+	SchemeBuilder      = runtime.NewSchemeBuilder(addKnownTypes)
+	localSchemeBuilder = &SchemeBuilder
+	AddToScheme        = SchemeBuilder.AddToScheme
 )
 
 func addKnownTypes(scheme *runtime.Scheme) error {