Recreate WebrtcVideoSendStream if screen content setting is changed.

webrtc/media/engine/webrtcvideoengine2.cc

Index: webrtc/media/engine/webrtcvideoengine2.cc
diff --git a/webrtc/media/engine/webrtcvideoengine2.cc b/webrtc/media/engine/webrtcvideoengine2.cc
index c192b52402ee95ef3f2ffd9dbe25f65ded5ecf6d..02063954921b28a228a7de8a6dbc576c042a9154 100644
--- a/webrtc/media/engine/webrtcvideoengine2.cc
+++ b/webrtc/media/engine/webrtcvideoengine2.cc
@@ -1612,7 +1612,15 @@ bool WebRtcVideoChannel2::WebRtcVideoSendStream::SetVideoSend(
   if (options_present) {
     VideoOptions old_options = parameters_.options;
     parameters_.options.SetAll(*options);
-    if (parameters_.options != old_options) {
+    if (parameters_.options.is_screencast.value_or(false) !=
+            old_options.is_screencast.value_or(false) &&
+        parameters_.codec_settings) {
+      // If screen content settings change, we may need to recreate the codec
+      // instance so that the correct type is used. Add a param to force the
+      // SetCodec() to not resuse the current instance.
+      allocated_encoder_.codec.params["recreate"] = "true";
+      SetCodec(*parameters_.codec_settings);
+    } else if (parameters_.options != old_options) {
       ReconfigureEncoder();
     }
   }