Remove references to libpeerconnection.

What used to be the libpeerconnection library is now compiled
statically into the Chromium binary, so clean up references it.

BUG=chromium:482123
TBR=tommi@webrtc.org

Review URL: https://codereview.webrtc.org/1399513002 .

Cr-Original-Commit-Position: refs/heads/master@{#10216}
Cr-Mirrored-From: https://chromium.googlesource.com/external/webrtc
Cr-Mirrored-Commit: 6ffc3309dee47b31ba118e41acc89a258c754c33
1 file changed