This CL adds methods to manipulate RTP header extension, particularly

content/browser/renderer_host/p2p/socket_host.h

Index: content/browser/renderer_host/p2p/socket_host.h
diff --git a/content/browser/renderer_host/p2p/socket_host.h b/content/browser/renderer_host/p2p/socket_host.h
index 46fcde5b7d56a22a815f1a0cf850b2fa538c4252..e18a5d998365c659384753e879a07d012408a0bf 100644
--- a/content/browser/renderer_host/p2p/socket_host.h
+++ b/content/browser/renderer_host/p2p/socket_host.h
@@ -53,6 +53,9 @@ class CONTENT_EXPORT P2PSocketHost {
   virtual bool SetOption(P2PSocketOption option, int value) = 0;
 
  protected:
+  void MaybeUpdateRtpSendTimeExtn(char* data, int length,
+                                  const talk_base::PacketOptions& options);
+
   friend class P2PSocketHostTcpTestBase;
 
   // TODO(mallinath) - Remove this below enum and use one defined in
@@ -97,6 +100,14 @@ class CONTENT_EXPORT P2PSocketHost {
                                 StunMessageType* type);
   static bool IsRequestOrResponse(StunMessageType type);
 
+  bool UpdateRtpAbsSendTimeExtension(char* data, int length,

[juberti2, 2014/02/22 01:16:05]

This should probably also be a Maybe function. 

Perhaps call the first function MaybeUpdatePacketSendTimeExtn, the second
MaybeUpdateRtpSendTimeExtn, and the last UpdateSendTimeExtnValue.

The last function should be MaybeUpdateRtpAuthTag

[Mallinath (Gone from Chromium), 2014/02/25 00:20:02]

Done.

+                                     const int extension_id);

[juberti2, 2014/02/22 01:16:05]

const not needed on value types

[Mallinath (Gone from Chromium), 2014/02/25 00:20:02]

Done.

+  bool GetRtpPacketStartPosition(char* data, int length, int* rtp_start_pos);
+  void UpdateAbsSendtime(char* data, int len);
+
+  void UpdateHmac(char* packet, int len,
+                  const talk_base::PacketOptions& options);
+
   IPC::Sender* message_sender_;
   int id_;
   State state_;