[Chromoting] Implement new APIs in DesktopCapturer

remoting/host/desktop_capturer_proxy.cc

Index: remoting/host/desktop_capturer_proxy.cc
diff --git a/remoting/host/desktop_capturer_proxy.cc b/remoting/host/desktop_capturer_proxy.cc
index 6030a64a16844bcc1a79d2c089b5e7a6606dacde..6a89c54964e5bd83e60630d641242510eca0cfc4 100644
--- a/remoting/host/desktop_capturer_proxy.cc
+++ b/remoting/host/desktop_capturer_proxy.cc
@@ -166,6 +166,14 @@ void DesktopCapturerProxy::CaptureFrame() {
       base::Bind(&Core::CaptureFrame, base::Unretained(core_.get())));
 }
 
+bool DesktopCapturerProxy::GetSourceList(SourceList* sources) {
+  return false;
+}
+
+bool DesktopCapturerProxy::SelectSource(SourceId id) {
+  return false;
+}
+
 void DesktopCapturerProxy::OnFrameCaptured(
     webrtc::DesktopCapturer::Result result,
     std::unique_ptr<webrtc::DesktopFrame> frame) {