Introduce AudioDecoderConfig to migrate away from GetAVStream().

media/base/audio_decoder_config.cc

Index: media/base/audio_decoder_config.cc
diff --git a/media/base/audio_decoder_config.cc b/media/base/audio_decoder_config.cc
new file mode 100644
index 0000000000000000000000000000000000000000..80b23e2abdcbec3ecc12987424965578652b5561
--- /dev/null
+++ b/media/base/audio_decoder_config.cc
@@ -0,0 +1,87 @@
+// Copyright (c) 2011 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/base/audio_decoder_config.h"
+
+#include "base/logging.h"
+#include "media/base/limits.h"
+
+namespace media {
+
+AudioDecoderConfig::AudioDecoderConfig()
+    : codec_(kUnknownAudioCodec),
+      bits_per_channel_(0),
+      channel_layout_(CHANNEL_LAYOUT_UNSUPPORTED),
+      samples_per_second_(0),
+      extra_data_size_(0) {
+}
+
+AudioDecoderConfig::AudioDecoderConfig(AudioCodec codec,
+                                       int bits_per_channel,
+                                       ChannelLayout channel_layout,
+                                       int samples_per_second,
+                                       const uint8* extra_data,
+                                       size_t extra_data_size) {
+  Initialize(codec, bits_per_channel, channel_layout, samples_per_second,
+             extra_data, extra_data_size);
+}
+
+void AudioDecoderConfig::Initialize(AudioCodec codec,
+                                    int bits_per_channel,
+                                    ChannelLayout channel_layout,
+                                    int samples_per_second,
+                                    const uint8* extra_data,
+                                    size_t extra_data_size) {
+  CHECK((extra_data_size != 0) == (extra_data != NULL));
+
+  codec_ = codec;
+  bits_per_channel_ = bits_per_channel;
+  channel_layout_ = channel_layout;
+  samples_per_second_ = samples_per_second;
+  extra_data_size_ = extra_data_size;
+
+  if (extra_data_size_ > 0) {
+    extra_data_.reset(new uint8[extra_data_size_]);
+    memcpy(extra_data_.get(), extra_data, extra_data_size_);
+  } else {
+    extra_data_.reset();
+  }
+}
+
+AudioDecoderConfig::~AudioDecoderConfig() {}
+
+bool AudioDecoderConfig::IsValidConfig() const {
+  return codec_ != kUnknownAudioCodec &&
+      channel_layout_ != CHANNEL_LAYOUT_UNSUPPORTED &&
+      bits_per_channel_ > 0 &&
+      bits_per_channel_ <= Limits::kMaxBitsPerSample &&
+      samples_per_second_ > 0 &&
+      samples_per_second_ <= Limits::kMaxSampleRate;
+}
+
+AudioCodec AudioDecoderConfig::codec() const {
+  return codec_;
+}
+
+int AudioDecoderConfig::bits_per_channel() const {
+  return bits_per_channel_;
+}
+
+ChannelLayout AudioDecoderConfig::channel_layout() const {
+  return channel_layout_;
+}
+
+int AudioDecoderConfig::samples_per_second() const {
+  return samples_per_second_;
+}
+
+uint8* AudioDecoderConfig::extra_data() const {
+  return extra_data_.get();
+}
+
+size_t AudioDecoderConfig::extra_data_size() const {
+  return extra_data_size_;
+}
+
+}  // namespace media