Add RTCP packet class for signaling encoder target bitrate.

webrtc/modules/rtp_rtcp/source/rtcp_packet/target_bitrate.h

Index: webrtc/modules/rtp_rtcp/source/rtcp_packet/target_bitrate.h
diff --git a/webrtc/modules/rtp_rtcp/source/rtcp_packet/target_bitrate.h b/webrtc/modules/rtp_rtcp/source/rtcp_packet/target_bitrate.h
new file mode 100644
index 0000000000000000000000000000000000000000..013c222f8e1b1db2b9f09fafffe06a7fe06c6417
--- /dev/null
+++ b/webrtc/modules/rtp_rtcp/source/rtcp_packet/target_bitrate.h
@@ -0,0 +1,60 @@
+/*
+ *  Copyright (c) 2016 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.
+ */
+
+#ifndef WEBRTC_MODULES_RTP_RTCP_SOURCE_RTCP_PACKET_TARGET_BITRATE_H_
+#define WEBRTC_MODULES_RTP_RTCP_SOURCE_RTCP_PACKET_TARGET_BITRATE_H_
+
+#include <vector>
+
+#include "webrtc/base/basictypes.h"
+
+namespace webrtc {
+namespace rtcp {
+
+class TargetBitrate {
+ public:
+  // TODO(sprang): This block type is just a place holder. We need to get an
+  //               id assigned by IANA.
+  static constexpr uint8_t kBlockType = 42;
+  static const size_t kBitrateItemSizeBytes;
+
+  struct BitrateItem {
+    BitrateItem();
+    BitrateItem(uint8_t spatial_layer,
+                uint8_t temporal_layer,
+                uint32_t target_bitrate_kbps);
+
+    uint8_t spatial_layer;
+    uint8_t temporal_layer;
+    uint32_t target_bitrate_kbps;
+  };
+
+  TargetBitrate();
+  ~TargetBitrate();
+
+  void AddTargetBitrate(uint8_t spatial_layer,
+                        uint8_t temporal_layer,
+                        uint32_t target_bitrate_kbps);
+
+  const std::vector<BitrateItem>& GetTargetBitrates() const;
+
+  bool Parse(const uint8_t* block, uint16_t block_length);
+
+  void Create(uint8_t* buffer) const;
+
+  size_t BlockLength() const;
+
+ private:
+  std::vector<BitrateItem> bitrates_;
+};
+
+}  // namespace rtcp
+}  // namespace webrtc
+#endif  // WEBRTC_MODULES_RTP_RTCP_SOURCE_RTCP_PACKET_TARGET_BITRATE_H_