Fix build by including trace_event_internal in webrtc namespace
Fix build by including trace_event_internal in webrtc namespace

TBR=ajm@webrtc.org
Review URL: https://webrtc-codereview.appspot.com/969017

Cr-Mirrored-From: https://chromium.googlesource.com/external/webrtc
Cr-Mirrored-Commit: 770a01e3b028582e19ec1af130bc7a1c6931dab6

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