Enable setting the maximum bitrate limit in RtpSender.

webrtc/media/base/mediaengine.cc

Index: webrtc/media/base/mediaengine.cc
diff --git a/webrtc/media/base/mediaengine.cc b/webrtc/media/base/mediaengine.cc
index df17ee783992373b4193d23fd7d4676b27571284..4027137565e10a179688e0c0283835e65eb95cc3 100644
--- a/webrtc/media/base/mediaengine.cc
+++ b/webrtc/media/base/mediaengine.cc
@@ -35,3 +35,14 @@ MediaEngineFactory::MediaEngineCreateFunction
 };  // namespace cricket
 
 #endif  // DISABLE_MEDIA_ENGINE_FACTORY
+
+namespace cricket {
+
+webrtc::RtpParameters CreateRtpParametersWithOneEncoding() {
+  webrtc::RtpParameters parameters;
+  webrtc::RtpEncodingParameters encoding;
+  parameters.encodings.push_back(encoding);
+  return parameters;
+}
+
+};  // namespace cricket