vendor cleanup: remove unused,non-go and test files

vendor/k8s.io/apimachinery/pkg/util/waitgroup/waitgroup.go

@@ -1,57 +0,0 @@
-/*
-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 waitgroup
-
-import (
-	"fmt"
-	"sync"
-)
-
-// SafeWaitGroup must not be copied after first use.
-type SafeWaitGroup struct {
-	wg sync.WaitGroup
-	mu sync.RWMutex
-	// wait indicate whether Wait is called, if true,
-	// then any Add with positive delta will return error.
-	wait bool
-}
-
-// Add adds delta, which may be negative, similar to sync.WaitGroup.
-// If Add with a positive delta happens after Wait, it will return error,
-// which prevent unsafe Add.
-func (wg *SafeWaitGroup) Add(delta int) error {
-	wg.mu.RLock()
-	defer wg.mu.RUnlock()
-	if wg.wait && delta > 0 {
-		return fmt.Errorf("add with positive delta after Wait is forbidden")
-	}
-	wg.wg.Add(delta)
-	return nil
-}
-
-// Done decrements the WaitGroup counter.
-func (wg *SafeWaitGroup) Done() {
-	wg.wg.Done()
-}
-
-// Wait blocks until the WaitGroup counter is zero.
-func (wg *SafeWaitGroup) Wait() {
-	wg.mu.Lock()
-	wg.wait = true
-	wg.mu.Unlock()
-	wg.wg.Wait()
-}