Charge quota for uninitialized objects at different time

Charge object count when object is created, no matter if the object is
initialized or not.
Charge the remaining quota when the object is initialized.

Also, checking initializer.Pending and initializer.Result when
determining if an object is initialized. We didn't need to check them
because before 51082, having 0 pending initializer and nil
initializers.Result is invalid.

staging/src/k8s.io/apimachinery/pkg/util/initialization/initialization.go

@@ -0,0 +1,48 @@
+/*
+Copyright 2017 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package initialization
+
+import (
+	"k8s.io/apimachinery/pkg/api/meta"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/apimachinery/pkg/runtime"
+)
+
+// IsInitialized returns if the initializers indicates means initialized.
+func IsInitialized(initializers *metav1.Initializers) bool {
+	if initializers == nil {
+		return true
+	}
+	// Persisted objects will never be in this state. The initializer admission
+	// plugin will override metadata.initializers to nil. If the initializer
+	// admissio plugin is disabled, the generic registry always set
+	// metadata.initializers to nil. However, this function
+	// might be called before the object persisted, thus the check.
+	if len(initializers.Pending) == 0 && initializers.Result == nil {
+		return true
+	}
+	return false
+}
+
+// IsObjectInitialized returns if the object is initialized.
+func IsObjectInitialized(obj runtime.Object) (bool, error) {
+	accessor, err := meta.Accessor(obj)
+	if err != nil {
+		return false, err
+	}
+	return IsInitialized(accessor.GetInitializers()), nil
+}