Expose ILBC codec in webrtc/api/audio_codecs/

webrtc/api/audio_codecs/ilbc/audio_decoder_ilbc.cc

+/*
+ *  Copyright (c) 2017 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+#include "webrtc/api/audio_codecs/ilbc/audio_decoder_ilbc.h"
+
+#include <memory>
+#include <vector>
+
+#include "webrtc/base/ptr_util.h"
+#include "webrtc/common_types.h"
+#include "webrtc/modules/audio_coding/codecs/ilbc/audio_decoder_ilbc.h"
+
+namespace webrtc {
+
+rtc::Optional<AudioDecoderIlbc::Config> AudioDecoderIlbc::SdpToConfig(
+    const SdpAudioFormat& format) {
+  return STR_CASE_CMP(format.name.c_str(), "ilbc") == 0 &&
+                 format.clockrate_hz == 8000 && format.num_channels == 1
+             ? rtc::Optional<Config>(Config())
+             : rtc::Optional<Config>();
+}
+
+void AudioDecoderIlbc::AppendSupportedDecoders(
+    std::vector<AudioCodecSpec>* specs) {
+  specs->push_back({{"ILBC", 8000, 1}, {8000, 1, 13300}});
+}
+
+std::unique_ptr<AudioDecoder> AudioDecoderIlbc::MakeAudioDecoder(
+    Config config) {
+  return rtc::MakeUnique<AudioDecoderIlbcImpl>();
+}
+
+}  // namespace webrtc