Fix for Heap-use-after-free in webrtc::voe::Channel::SendRTCPPacket
Fix for Heap-use-after-free in webrtc::voe::Channel::SendRTCPPacket

Ensures that we always call DeRegisterExternalTransport() even if a fuzz test calls DeRegisterExternalTransport in an unintialized state.

TBR=tommi
BUG=296804 in crbug.com

Review URL: https://webrtc-codereview.appspot.com/2275008

Cr-Mirrored-From: https://chromium.googlesource.com/external/webrtc
Cr-Mirrored-Commit: 9b6eefcedf3603c9c7b1bd424653ae0a08c1a9f4

sippet/webrtc,sippet/webrtc,sippet/webrtc,sippet/webrtc,sippet/webrtc,sippet/webrtc