Replace SetCapturer and SetCaptureDevice by SetSource.
Drop return value.

BUG=webrtc:5426

Review URL: https://codereview.webrtc.org/1766653002

Cr-Commit-Position: refs/heads/master@{#12291}
diff --git a/webrtc/api/webrtcsession_unittest.cc b/webrtc/api/webrtcsession_unittest.cc
index f4b41d3..28f93df 100644
--- a/webrtc/api/webrtcsession_unittest.cc
+++ b/webrtc/api/webrtcsession_unittest.cc
@@ -246,7 +246,7 @@
 
   using webrtc::WebRtcSession::SetAudioPlayout;
   using webrtc::WebRtcSession::SetAudioSend;
-  using webrtc::WebRtcSession::SetCaptureDevice;
+  using webrtc::WebRtcSession::SetSource;
   using webrtc::WebRtcSession::SetVideoPlayout;
   using webrtc::WebRtcSession::SetVideoSend;