Version: M52 Canary 52.0.2743.0
OS: Mac 10.11.5

What steps will reproduce the problem?
(1) Start an apprtc loopback call with vsc=h264 param appended to it https://appr.tc/?debug=loopback&vsc=h264
(2) Open up chrome://webrtc-internals and expand the ssrc_send video 
(3) alternatively, in the apprtc lopback call, see the codec type in the call info overlay, accessed via keyboard shortcut “i”.

What is the expected output?
in webrtc-internals, googCodecName should be H264, and the call overlay should show Video Tx as H264

What do you see instead?
both in webrtc-internals and call overlay, the codec name is VP9


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