There are still a few places in VideoReceiveStream where the RTP module
is explicitly used, e.g. setting up a/v sync, but it's a bigger task to
change and that will be done in a follow up instead of in this CL.
BUG=webrtc:5838
Review-Url: https://codereview.webrtc.org/1947913002
Cr-Commit-Position: refs/heads/master@{#12642}
ViEChannel is now called VideoStreamReceiver.
There will be a follow up CL removing all rtp references from VideoReceiveStream, but that made this CL to big and it will be done separately.
BUG=webrtc:5079
Review-Url: https://codereview.webrtc.org/1929313002
Cr-Commit-Position: refs/heads/master@{#12619}
