Wire up RTP keep-alive in ortc api.

webrtc/media/engine/fakewebrtccall.cc

Index: webrtc/media/engine/fakewebrtccall.cc
diff --git a/webrtc/media/engine/fakewebrtccall.cc b/webrtc/media/engine/fakewebrtccall.cc
index 2e793b85253800211b4ca7414ccdeed43aa52df3..aa302795ec52ea8414ec227474f66201759efeb4 100644
--- a/webrtc/media/engine/fakewebrtccall.cc
+++ b/webrtc/media/engine/fakewebrtccall.cc
@@ -637,4 +637,12 @@ void FakeCall::OnSentPacket(const rtc::SentPacket& sent_packet) {
   }
 }
 
+bool FakeCall::SetRtpKeepAliveConfig(const webrtc::RtpKeepAliveConfig& config) {
+  if ((config != config_.keepalive_config) && num_created_send_streams_ > 0)
+    return false;
+
+  config_.keepalive_config = config;
+  return true;
+}
+
 }  // namespace cricket