Add a libfuzzer for RtpHeaderParser.

webrtc/modules/rtp_rtcp/include/rtp_rtcp_defines.h

 /*
  *  Copyright (c) 2012 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.
  */
 
@@ skipping 42 matching lines @@
 enum ProtectionType {
   kUnprotectedPacket,
   kProtectedPacket
 };
 
 enum StorageType {
   kDontRetransmit,
   kAllowRetransmission
 };
 
+const int kNumberOfRtpHeaderExtensions = 7;

[danilchap, 2016/06/15 09:18:14]

make it constexpr, and it should be 6 (there are 6 supported extensions now:
None is not an extension)

 enum RTPExtensionType {
   kRtpExtensionNone,
   kRtpExtensionTransmissionTimeOffset,
   kRtpExtensionAudioLevel,
   kRtpExtensionAbsoluteSendTime,
   kRtpExtensionVideoRotation,
   kRtpExtensionTransportSequenceNumber,
   kRtpExtensionPlayoutDelay,
 };
 
@@ skipping 327 matching lines @@
 class TransportSequenceNumberAllocator {
  public:
   TransportSequenceNumberAllocator() {}
   virtual ~TransportSequenceNumberAllocator() {}
 
   virtual uint16_t AllocateSequenceNumber() = 0;
 };
 
 }  // namespace webrtc
 #endif  // WEBRTC_MODULES_RTP_RTCP_INCLUDE_RTP_RTCP_DEFINES_H_