Revert of make the DtlsTransportWrapper inherit form DtlsTransportInternal

webrtc/p2p/base/dtlstransportinternal.h

Index: webrtc/p2p/base/dtlstransportinternal.h
diff --git a/webrtc/p2p/base/dtlstransportinternal.h b/webrtc/p2p/base/dtlstransportinternal.h
index 74fdd6dfcfd9403bc431006bfbe178566833bb4f..780c128e0068fbc2b7c3ceb48a395bc268c054dc 100644
--- a/webrtc/p2p/base/dtlstransportinternal.h
+++ b/webrtc/p2p/base/dtlstransportinternal.h
@@ -21,12 +21,6 @@
 #include "webrtc/p2p/base/packettransportinterface.h"
 
 namespace cricket {
-
-enum PacketFlags {
-  PF_NORMAL = 0x00,       // A normal packet.
-  PF_SRTP_BYPASS = 0x01,  // An encrypted SRTP packet; bypass any additional
-                          // crypto provided by the transport (e.g. DTLS)
-};
 
 // DtlsTransportInternal is an internal interface that does DTLS.
 // Once the public interface is supported,
@@ -100,9 +94,6 @@
     return transport_name() + " " + std::to_string(component());
   }
 
- protected:
-  DtlsTransportInternal() {}
-
  private:
   RTC_DISALLOW_COPY_AND_ASSIGN(DtlsTransportInternal);
 };