Revert "EDK: Move //mojo/edk/system/waitable_event* to edk/util."

mojo/edk/system/test_channel_endpoint_client.cc

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "mojo/edk/system/test_channel_endpoint_client.h"
 
 #include <utility>
 
 #include "mojo/edk/system/message_in_transit.h"
-#include "mojo/edk/util/waitable_event.h"
+#include "mojo/edk/system/waitable_event.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
-using mojo::util::ManualResetWaitableEvent;
 using mojo::util::MutexLocker;
 using mojo::util::RefPtr;
 
 namespace mojo {
 namespace system {
 namespace test {
 
 void TestChannelEndpointClient::Init(unsigned port,
                                      RefPtr<ChannelEndpoint>&& endpoint) {
   MutexLocker locker(&mutex_);
@@ skipping 52 matching lines @@
 TestChannelEndpointClient::TestChannelEndpointClient()
     : port_(0), read_event_(nullptr) {}
 
 TestChannelEndpointClient::~TestChannelEndpointClient() {
   EXPECT_FALSE(endpoint_);
 }
 
 }  // namespace test
 }  // namespace system
 }  // namespace mojo