Fix WebRTC API framework build.

BUG=webrtc:5737

Review URL: https://codereview.webrtc.org/1875003004

Cr-Original-Commit-Position: refs/heads/master@{#12391}
Cr-Mirrored-From: https://chromium.googlesource.com/external/webrtc
Cr-Mirrored-Commit: 5209d671f2597e88004ad7acd097294d9460ce7f
13 files changed