Add AudioEncoder::GetTargetBitrate

webrtc/modules/audio_coding/codecs/pcm16b/audio_encoder_pcm16b.cc

Index: webrtc/modules/audio_coding/codecs/pcm16b/audio_encoder_pcm16b.cc
diff --git a/webrtc/modules/audio_coding/codecs/pcm16b/audio_encoder_pcm16b.cc b/webrtc/modules/audio_coding/codecs/pcm16b/audio_encoder_pcm16b.cc
index 491fdfdb14fb7369c479c02a4efc3470b0c07dce..f0c8de4b931db19e5cbd3b9c40072db767496712 100644
--- a/webrtc/modules/audio_coding/codecs/pcm16b/audio_encoder_pcm16b.cc
+++ b/webrtc/modules/audio_coding/codecs/pcm16b/audio_encoder_pcm16b.cc
@@ -23,6 +23,10 @@ bool AudioEncoderPcm16B::Config::IsOk() const {
   return AudioEncoderPcm::Config::IsOk();
 }
 
+int AudioEncoderPcm16B::SetTargetBitrate(int bits_per_second) {
+  return 16 * SampleRateHz() * NumChannels();  // 16 bits per sample.
+}
+
 int16_t AudioEncoderPcm16B::EncodeCall(const int16_t* audio,
                                        size_t input_len,
                                        uint8_t* encoded) {