Make SharedMemory track the size that was actually mapped

content/browser/renderer_host/media/audio_sync_reader.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 "content/browser/renderer_host/media/audio_sync_reader.h"
 
 #include <algorithm>
 
 #include "base/metrics/histogram.h"
 #include "base/process_util.h"
 #include "base/shared_memory.h"
 #include "media/audio/audio_buffers_state.h"
 #include "media/audio/audio_parameters.h"
 #include "media/audio/shared_memory_util.h"
 
 using media::AudioBus;
 
 namespace content {
 
 AudioSyncReader::AudioSyncReader(base::SharedMemory* shared_memory,
                                  const media::AudioParameters& params,
                                  int input_channels)
     : shared_memory_(shared_memory),
       input_channels_(input_channels),
       renderer_callback_count_(0),
       renderer_missed_callback_count_(0) {
-  packet_size_ = media::PacketSizeInBytes(shared_memory_->created_size());
+  packet_size_ = media::PacketSizeInBytes(shared_memory_->requested_size());
   int input_memory_size = 0;
   int output_memory_size = AudioBus::CalculateMemorySize(params);
   if (input_channels_ > 0) {
     // The input storage is after the output storage.
     int frames = params.frames_per_buffer();
     input_memory_size = AudioBus::CalculateMemorySize(input_channels_, frames);
     char* input_data =
         static_cast<char*>(shared_memory_->memory()) + output_memory_size;
     input_bus_ = AudioBus::WrapMemory(input_channels_, frames, input_data);
   }
@@ skipping 110 matching lines @@
     base::FileDescriptor* foreign_handle) {
   foreign_handle->fd = foreign_socket_->handle();
   foreign_handle->auto_close = false;
   if (foreign_handle->fd != -1)
     return true;
   return false;
 }
 #endif
 
 }  // namespace content