Remove unneeded CountDownLatch class.

Sources/gRPC/CountDownLatch.swift

@@ -1,48 +0,0 @@
-/*
- * Copyright 2016, gRPC Authors All rights reserved.
- *
- * 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.
- */
-import Foundation
-
-/// A synchronization primitive used to synchronize gRPC operations
-/// Initialize it with a count, a call to wait() will block until
-/// signal() has been called the specified number of times.
-public class CountDownLatch {
-  private var condition : NSCondition
-  private var count : Int
-
-  public init(_ count : Int) {
-    self.condition = NSCondition()
-    self.count = count
-  }
-
-  public func signal() {
-    self.condition.lock()
-    self.count = self.count - 1
-    self.condition.signal()
-    self.condition.unlock()
-  }
-
-  public func wait() {
-    var running = true
-    while (running) {
-      self.condition.lock()
-      self.condition.wait()
-      if (self.count == 0) {
-        running = false
-      }
-      self.condition.unlock()
-    }
-  }
-}