Let ViEEncoder handle resolution changes.

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 9437fa0fbaec234ec1d81d6815e0da795a84240f..fd4292eb1b45382830ab40b3178058cb3260bc5a 100644
--- a/webrtc/media/engine/fakewebrtccall.cc
+++ b/webrtc/media/engine/fakewebrtccall.cc
@@ -123,8 +123,9 @@ const webrtc::VideoEncoderConfig& FakeVideoSendStream::GetEncoderConfig()
   return encoder_config_;
 }
 
-std::vector<webrtc::VideoStream> FakeVideoSendStream::GetVideoStreams() {
-  return encoder_config_.streams;
+const std::vector<webrtc::VideoStream>& FakeVideoSendStream::GetVideoStreams()
+    const {
+  return video_streams_;
 }
 
 bool FakeVideoSendStream::IsSending() const {
@@ -170,6 +171,13 @@ int64_t FakeVideoSendStream::GetLastTimestamp() const {
 
 void FakeVideoSendStream::OnFrame(const webrtc::VideoFrame& frame) {
   ++num_swapped_frames_;
+  if (frame.width() != last_frame_.width() ||
+      frame.height() != last_frame_.height() ||
+      frame.rotation() != last_frame_.rotation()) {
+    video_streams_ =
+        encoder_config_.encoder_stream_factory->CreateEncoderStreams(
+            frame.width(), frame.height(), encoder_config_);
+  }
   last_frame_.ShallowCopy(frame);
 }
 
@@ -184,29 +192,31 @@ webrtc::VideoSendStream::Stats FakeVideoSendStream::GetStats() {
 
 void FakeVideoSendStream::ReconfigureVideoEncoder(
     webrtc::VideoEncoderConfig config) {
+  video_streams_ = config.encoder_stream_factory->CreateEncoderStreams(
+      last_frame_.width(), last_frame_.height(), config);
+  encoder_config_ = std::move(config);
+  codec_settings_set_ = config.encoder_specific_settings != nullptr;
+  ++num_encoder_reconfigurations_;
   if (config.encoder_specific_settings != NULL) {
     if (config_.encoder_settings.payload_name == "VP8") {
       vpx_settings_.vp8 = *reinterpret_cast<const webrtc::VideoCodecVP8*>(
                               config.encoder_specific_settings);
-      if (!config.streams.empty()) {
+      if (!video_streams_.empty()) {
         vpx_settings_.vp8.numberOfTemporalLayers = static_cast<unsigned char>(
-            config.streams.back().temporal_layer_thresholds_bps.size() + 1);
+            video_streams_.back().temporal_layer_thresholds_bps.size() + 1);
       }
     } else if (config_.encoder_settings.payload_name == "VP9") {
       vpx_settings_.vp9 = *reinterpret_cast<const webrtc::VideoCodecVP9*>(
-                              config.encoder_specific_settings);
-      if (!config.streams.empty()) {
+          config.encoder_specific_settings);
+      if (!video_streams_.empty()) {
         vpx_settings_.vp9.numberOfTemporalLayers = static_cast<unsigned char>(
-            config.streams.back().temporal_layer_thresholds_bps.size() + 1);
+            video_streams_.back().temporal_layer_thresholds_bps.size() + 1);
       }
     } else {
       ADD_FAILURE() << "Unsupported encoder payload: "
                     << config_.encoder_settings.payload_name;
     }
   }
-  encoder_config_ = std::move(config);
-  codec_settings_set_ = config.encoder_specific_settings != NULL;
-  ++num_encoder_reconfigurations_;
 }
 
 void FakeVideoSendStream::Start() {