Revert of Make rtcp parsing implementation private in RtcpReceiver (patchset #1 id:1 of https://codereview.webrtc.org/2320603002/ )

Reason for revert:
Breaks fuzzer compilation.

Original issue's description:
> Make rtcp parsing implementation private in RtcpReceiver:
> Function just for Parse and for Callbacks moved to private section.
> All handles moved from protected to private section.
>
> BUG=webrtc:5260
> R=sprang@webrtc.org
>
> Committed: https://crrev.com/faf708e238c7b43a732fbebf79ac9298b4b95a95
> Cr-Commit-Position: refs/heads/master@{#14181}

TBR=sprang@webrtc.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=webrtc:5260

Review-Url: https://codereview.webrtc.org/2332673003
Cr-Commit-Position: refs/heads/master@{#14182}
diff --git a/webrtc/modules/rtp_rtcp/source/rtcp_receiver.h b/webrtc/modules/rtp_rtcp/source/rtcp_receiver.h
index e9d2c94..3659374 100644
--- a/webrtc/modules/rtp_rtcp/source/rtcp_receiver.h
+++ b/webrtc/modules/rtp_rtcp/source/rtcp_receiver.h
@@ -60,6 +60,13 @@
   void SetRemoteSSRC(uint32_t ssrc);
   uint32_t RemoteSSRC() const;
 
+  int32_t IncomingRTCPPacket(
+      RTCPHelp::RTCPPacketInformation& rtcpPacketInformation,
+      RTCPUtility::RTCPParserV2* rtcpParser);
+
+  void TriggerCallbacksFromRTCPPacket(
+      RTCPHelp::RTCPPacketInformation& rtcpPacketInformation);
+
   // get received cname
   int32_t CNAME(uint32_t remoteSSRC, char cName[RTCP_CNAME_SIZE]) const;
 
@@ -108,21 +115,7 @@
   void RegisterRtcpStatisticsCallback(RtcpStatisticsCallback* callback);
   RtcpStatisticsCallback* GetRtcpStatisticsCallback();
 
- private:
-  using ReceivedInfoMap = std::map<uint32_t, RTCPHelp::RTCPReceiveInformation*>;
-  // RTCP report block information mapped by remote SSRC.
-  using ReportBlockInfoMap =
-      std::map<uint32_t, RTCPHelp::RTCPReportBlockInformation*>;
-  // RTCP report block information map mapped by source SSRC.
-  using ReportBlockMap = std::map<uint32_t, ReportBlockInfoMap>;
-
-  int32_t IncomingRTCPPacket(
-      RTCPHelp::RTCPPacketInformation& rtcpPacketInformation,
-      RTCPUtility::RTCPParserV2* rtcpParser);
-
-  void TriggerCallbacksFromRTCPPacket(
-      RTCPHelp::RTCPPacketInformation& rtcpPacketInformation);
-
+ protected:
   RTCPUtility::RTCPCnameInformation* CreateCnameInformation(
       uint32_t remoteSSRC);
   RTCPUtility::RTCPCnameInformation* GetCnameInformation(
@@ -260,6 +253,14 @@
       RTCPHelp::RTCPPacketInformation* rtcp_packet_information)
       EXCLUSIVE_LOCKS_REQUIRED(_criticalSectionRTCPReceiver);
 
+ private:
+  typedef std::map<uint32_t, RTCPHelp::RTCPReceiveInformation*> ReceivedInfoMap;
+  // RTCP report block information mapped by remote SSRC.
+  typedef std::map<uint32_t, RTCPHelp::RTCPReportBlockInformation*>
+      ReportBlockInfoMap;
+  // RTCP report block information map mapped by source SSRC.
+  typedef std::map<uint32_t, ReportBlockInfoMap> ReportBlockMap;
+
   RTCPHelp::RTCPReportBlockInformation* CreateOrGetReportBlockInformation(
       uint32_t remote_ssrc,
       uint32_t source_ssrc)