Refactoring: Merge VideoSenderConfig and AudioSenderConfig.

media/cast/cast_config.cc

Index: media/cast/cast_config.cc
diff --git a/media/cast/cast_config.cc b/media/cast/cast_config.cc
index 1a619fd0703985f49a2ac06d73765ae1a81fb717..2535170800beea13fea405983e61e788e257e4a9 100644
--- a/media/cast/cast_config.cc
+++ b/media/cast/cast_config.cc
@@ -4,85 +4,50 @@
 
 #include "media/cast/cast_config.h"
 
-namespace {
-
-const float kDefaultCongestionControlBackOff = 0.875f;
-
-enum {
-  // Minimum and Maximum VP8 quantizer in default configuration.
-  kDefaultMaxQp = 63,
-  kDefaultMinQp = 4,
-
-  kDefaultMaxCpuSaverQp = 25,
-
-  // Number of video buffers in default configuration (applies only to certain
-  // external codecs).
-  kDefaultNumberOfVideoBuffers = 1,
-};
-
-}  // namespace
-
 namespace media {
 namespace cast {
 
-// TODO(miu): Revisit code factoring of these structs.  There are a number of
-// common elements between them all, so it might be reasonable to only have one
-// or two structs; or, at least a common base class.
-
-// TODO(miu): Make sure all POD members are initialized by ctors.  Policy
-// decision: Reasonable defaults or use invalid placeholder values to expose
-// unset members?
-
-// TODO(miu): Provide IsValidConfig() functions?
-
-// TODO(miu): Throughout the code, there is a lot of copy-and-paste of the same
-// calculations based on these config values.  So, why don't we add methods to
-// these classes to centralize the logic?
-
-VideoSenderConfig::VideoSenderConfig()
-    : ssrc(0),
-      receiver_ssrc(0),
-      max_playout_delay(
-          base::TimeDelta::FromMilliseconds(kDefaultRtpMaxDelayMs)),
-      rtp_payload_type(0),
-      use_external_encoder(false),
-      congestion_control_back_off(kDefaultCongestionControlBackOff),
-      max_bitrate(kDefaultMaxVideoKbps * 1000),
-      min_bitrate(kDefaultMinVideoKbps * 1000),
-      start_bitrate(kDefaultMaxVideoKbps * 1000),
+CodecSpecificParams::CodecSpecificParams()
+    : start_bitrate(0),
       max_qp(kDefaultMaxQp),
       min_qp(kDefaultMinQp),
       max_cpu_saver_qp(kDefaultMaxCpuSaverQp),
-      max_frame_rate(kDefaultMaxFrameRate),
       max_number_of_video_buffers_used(kDefaultNumberOfVideoBuffers),
-      codec(CODEC_VIDEO_VP8),
       number_of_encode_threads(1) {}
 
-VideoSenderConfig::VideoSenderConfig(const VideoSenderConfig& other) = default;
+CodecSpecificParams::CodecSpecificParams(const CodecSpecificParams& other) =
+    default;
 
-VideoSenderConfig::~VideoSenderConfig() {}
+CodecSpecificParams::~CodecSpecificParams() {}
 
-AudioSenderConfig::AudioSenderConfig()
-    : ssrc(0),
+// TODO(miu): Provide IsValidConfig() functions?
+
+FrameSenderConfig::FrameSenderConfig()
+    : sender_ssrc(0),
       receiver_ssrc(0),
+      min_playout_delay(
+          base::TimeDelta::FromMilliseconds(kDefaultRtpMaxDelayMs)),
       max_playout_delay(
           base::TimeDelta::FromMilliseconds(kDefaultRtpMaxDelayMs)),
-      rtp_payload_type(0),
+      animated_playout_delay(min_playout_delay),
+      rtp_payload_type(RtpPayloadType::UNKNOWN),
       use_external_encoder(false),
       frequency(0),
       channels(0),
-      bitrate(kDefaultAudioEncoderBitrate),
-      codec(CODEC_AUDIO_OPUS) {}
+      max_bitrate(0),
+      min_bitrate(0),
+      max_frame_rate(kDefaultMaxFrameRate),
+      codec(CODEC_UNKNOWN) {}
 
-AudioSenderConfig::AudioSenderConfig(const AudioSenderConfig& other) = default;
+FrameSenderConfig::FrameSenderConfig(const FrameSenderConfig& other) = default;
 
-AudioSenderConfig::~AudioSenderConfig() {}
+FrameSenderConfig::~FrameSenderConfig() {}
 
 FrameReceiverConfig::FrameReceiverConfig()
     : receiver_ssrc(0),
       sender_ssrc(0),
       rtp_max_delay_ms(kDefaultRtpMaxDelayMs),
-      rtp_payload_type(0),
+      rtp_payload_type(RtpPayloadType::UNKNOWN),
       rtp_timebase(0),
       channels(0),
       target_frame_rate(0),