Avoid unsafe usage of CancelIo() within Windows SyncSocket.

media/audio/audio_device_thread.cc

 // Copyright (c) 2012 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 "media/audio/audio_device_thread.h"
 
 #include <algorithm>
 
 #include "base/bind.h"
 #include "base/logging.h"
@@ skipping 148 matching lines @@
   // Release the reference for the thread. Note that after this, the Thread
   // instance will most likely be deleted.
   Release();
 }
 
 void AudioDeviceThread::Thread::Run() {
   uint32 buffer_index = 0;
   while (true) {
     int pending_data = 0;
     size_t bytes_read = socket_.Receive(&pending_data, sizeof(pending_data));
-    if (bytes_read != sizeof(pending_data)) {
-      DCHECK_EQ(bytes_read, 0U);
+    if (bytes_read != sizeof(pending_data))
       break;
-    }
 
     {
       base::AutoLock auto_lock(callback_lock_);
       if (callback_)
         callback_->Process(pending_data);
     }
 
     // Let the other end know which buffer we just filled.  The buffer index is
     // used to ensure the other end is getting the buffer it expects.  For more
     // details on how this works see AudioSyncReader::WaitUntilDataIsReady().
@@ skipping 29 matching lines @@
 }
 
 AudioDeviceThread::Callback::~Callback() {}
 
 void AudioDeviceThread::Callback::InitializeOnAudioThread() {
   MapSharedMemory();
   CHECK(shared_memory_.memory());
 }
 
 }  // namespace media.