Remove all the OS X 10.6 SDK forward declarations.

media/audio/mac/audio_output_mac.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/mac/audio_output_mac.h"
 
 #include <CoreServices/CoreServices.h>
 
 #include "base/basictypes.h"
 #include "base/debug/trace_event.h"
@@ skipping 20 matching lines @@
 // Then the OS queue is started which will create its own thread which
 // periodically will call the source for more data as buffers are being
 // consumed.
 // 4) At some point some thread will call Stop(), which we handle by directly
 // stoping the OS queue.
 // 5) One more callback to the source could be delivered in in the context of
 // the queue's own thread. Data, if any will be discared.
 // 6) The same thread that called stop will call Close() where we cleanup
 // and notifiy the audio manager, which likley will destroy this object.
 
-#if !defined(MAC_OS_X_VERSION_10_6) || \
-    MAC_OS_X_VERSION_MAX_ALLOWED < MAC_OS_X_VERSION_10_6
-enum {
-  kAudioQueueErr_EnqueueDuringReset = -66632
-};
-#endif
-
 PCMQueueOutAudioOutputStream::PCMQueueOutAudioOutputStream(
     AudioManagerMac* manager, const AudioParameters& params)
     : audio_queue_(NULL),
       source_(NULL),
       manager_(manager),
       packet_size_(params.GetBytesPerBuffer()),
       silence_bytes_(0),
       volume_(1),
       pending_bytes_(0),
       num_source_channels_(params.channels()),
@@ skipping 485 matching lines @@
   source_ = source;
 }
 
 AudioOutputStream::AudioSourceCallback*
 PCMQueueOutAudioOutputStream::GetSource() {
   base::AutoLock lock(source_lock_);
   return source_;
 }
 
 }  // namespace media