Updated structures and functions for setting the max bitrate limit to take rtc::Optional<int>

webrtc/media/engine/webrtcvideoengine2.h

Index: webrtc/media/engine/webrtcvideoengine2.h
diff --git a/webrtc/media/engine/webrtcvideoengine2.h b/webrtc/media/engine/webrtcvideoengine2.h
index 8c05c60f6823606a951783a5485adebef2e3dc1b..511a8234b84ea741dea1b398a5307199690263f0 100644
--- a/webrtc/media/engine/webrtcvideoengine2.h
+++ b/webrtc/media/engine/webrtcvideoengine2.h
@@ -192,7 +192,9 @@ class WebRtcVideoChannel2 : public VideoMediaChannel, public webrtc::Transport {
     // These optionals are unset if not changed.
     rtc::Optional<VideoCodecSettings> codec;
     rtc::Optional<std::vector<webrtc::RtpExtension>> rtp_header_extensions;
-    rtc::Optional<int> max_bandwidth_bps;
+    // The outer optional is unset if the bandwidth limit has not changed;
+    // the inner optional indicates if a bandwidth limit is in effect.
+    rtc::Optional<rtc::Optional<int>> max_bandwidth_bps;
     rtc::Optional<bool> conference_mode;
     rtc::Optional<webrtc::RtcpMode> rtcp_mode;
   };
@@ -239,7 +241,7 @@ class WebRtcVideoChannel2 : public VideoMediaChannel, public webrtc::Transport {
         const VideoOptions& options,
         WebRtcVideoEncoderFactory* external_encoder_factory,
         bool enable_cpu_overuse_detection,
-        int max_bitrate_bps,
+        rtc::Optional<int> max_bitrate_bps,
         const rtc::Optional<VideoCodecSettings>& codec_settings,
         const std::vector<webrtc::RtpExtension>& rtp_extensions,
         const VideoSendParameters& send_params);
@@ -274,11 +276,11 @@ class WebRtcVideoChannel2 : public VideoMediaChannel, public webrtc::Transport {
       VideoSendStreamParameters(
           const webrtc::VideoSendStream::Config& config,
           const VideoOptions& options,
-          int max_bitrate_bps,
+          rtc::Optional<int> max_bitrate_bps,
           const rtc::Optional<VideoCodecSettings>& codec_settings);
       webrtc::VideoSendStream::Config config;
       VideoOptions options;
-      int max_bitrate_bps;
+      rtc::Optional<int> max_bitrate_bps;
       bool conference_mode;
       rtc::Optional<VideoCodecSettings> codec_settings;
       // Sent resolutions + bitrates etc. by the underlying VideoSendStream,
@@ -319,12 +321,12 @@ class WebRtcVideoChannel2 : public VideoMediaChannel, public webrtc::Transport {
     static std::vector<webrtc::VideoStream> CreateVideoStreams(
         const VideoCodec& codec,
         const VideoOptions& options,
-        int max_bitrate_bps,
+        rtc::Optional<int> max_bitrate_bps,
         size_t num_streams);
     static std::vector<webrtc::VideoStream> CreateSimulcastVideoStreams(
         const VideoCodec& codec,
         const VideoOptions& options,
-        int max_bitrate_bps,
+        rtc::Optional<int> max_bitrate_bps,
         size_t num_streams);
 
     void* ConfigureVideoEncoderSettings(const VideoCodec& codec)