Reland "Move creating encoder to VideoStreamEncoder."

This is a reland of fb82fcc7f9c414dc8ba1ddd314e9524fee54cb80

Original change's description:
> Move creating encoder to VideoStreamEncoder.
>
> This used to be in WebRtcVideoChannel::WebRtcVideoSendStream.
> One implication is that encoder is not created until the first
> frame arrives, and some of the tests needed updates to emit a
> frame or two.
>
> Bug: webrtc:8830
> Change-Id: I78169b2bb4dfa4197b4b4229af9fd69d0f747835
> Reviewed-on: https://webrtc-review.googlesource.com/64885
> Commit-Queue: Niels Moller <nisse@webrtc.org>
> Reviewed-by: Erik Språng <sprang@webrtc.org>
> Reviewed-by: Karl Wiberg <kwiberg@webrtc.org>
> Cr-Commit-Position: refs/heads/master@{#22905}

TBR=magjed@webrtc.org,kwiberg@webrtc.org

Bug: webrtc:8830
Change-Id: I9565095ea1880fb49d15111198c08b2fcb84f18c
Reviewed-on: https://webrtc-review.googlesource.com/70740
Commit-Queue: Niels Moller <nisse@webrtc.org>
Reviewed-by: Niels Moller <nisse@webrtc.org>
Reviewed-by: Erik Språng <sprang@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#22930}

4 files changed, 10 insertions, 22 deletions

diff --git a/call/bitrate_estimator_tests.cc b/call/bitrate_estimator_tests.cc
index b4f808f30a..ea48a973ea 100644
--- a/call/bitrate_estimator_tests.cc
+++ b/call/bitrate_estimator_tests.cc
@@ -116,8 +116,8 @@ class BitrateEstimatorTest : public test::CallTest {
 
       video_send_config_ = VideoSendStream::Config(send_transport_.get());
       video_send_config_.rtp.ssrcs.push_back(kVideoSendSsrcs[0]);
-      // Encoders will be set separately per stream.
-      video_send_config_.encoder_settings.encoder = nullptr;
+      video_send_config_.encoder_settings.encoder_factory =
+          &fake_encoder_factory_;
       video_send_config_.rtp.payload_name = "FAKE";
       video_send_config_.rtp.payload_type = kFakeVideoSendPayloadType;
       test::FillEncoderConfiguration(kVideoCodecVP8, 1, &video_encoder_config_);
@@ -162,10 +162,8 @@ class BitrateEstimatorTest : public test::CallTest {
           is_sending_receiving_(false),
           send_stream_(nullptr),
           frame_generator_capturer_(),
-          fake_encoder_(Clock::GetRealTimeClock()),
           fake_decoder_() {
       test_->video_send_config_.rtp.ssrcs[0]++;
-      test_->video_send_config_.encoder_settings.encoder = &fake_encoder_;
       send_stream_ = test_->sender_call_->CreateVideoSendStream(
           test_->video_send_config_.Copy(),
           test_->video_encoder_config_.Copy());
@@ -223,7 +221,6 @@ class BitrateEstimatorTest : public test::CallTest {
     VideoSendStream* send_stream_;
     VideoReceiveStream* video_receive_stream_;
     std::unique_ptr<test::FrameGeneratorCapturer> frame_generator_capturer_;
-    test::FakeEncoder fake_encoder_;
     test::FakeDecoder fake_decoder_;
   };
 
diff --git a/call/call_perf_tests.cc b/call/call_perf_tests.cc
index 1337809db0..6520e6fcf9 100644
--- a/call/call_perf_tests.cc
+++ b/call/call_perf_tests.cc
@@ -29,6 +29,7 @@
 #include "test/call_test.h"
 #include "test/direct_transport.h"
 #include "test/drifting_clock.h"
+#include "test/encoder_proxy_factory.h"
 #include "test/encoder_settings.h"
 #include "test/fake_encoder.h"
 #include "test/field_trial.h"
@@ -637,7 +638,7 @@ void CallPerfTest::TestMinTransmitBitrate(bool pad_to_min_bitrate) {
     std::vector<double> bitrate_kbps_list_;
   } test(pad_to_min_bitrate);
 
-  fake_encoder_.SetMaxBitrate(kMaxEncodeBitrateKbps);
+  fake_encoder_max_bitrate_ = kMaxEncodeBitrateKbps;
   RunBaseTest(&test);
 }
 
@@ -686,7 +687,8 @@ TEST_F(CallPerfTest, MAYBE_KeepsHighBitrateWhenReconfiguringSender) {
           encoder_inits_(0),
           last_set_bitrate_kbps_(0),
           send_stream_(nullptr),
-          frame_generator_(nullptr) {}
+          frame_generator_(nullptr),
+          encoder_factory_(this) {}
 
     int32_t InitEncode(const VideoCodec* config,
                        int32_t number_of_cores,
@@ -735,7 +737,7 @@ TEST_F(CallPerfTest, MAYBE_KeepsHighBitrateWhenReconfiguringSender) {
         VideoSendStream::Config* send_config,
         std::vector<VideoReceiveStream::Config>* receive_configs,
         VideoEncoderConfig* encoder_config) override {
-      send_config->encoder_settings.encoder = this;
+      send_config->encoder_settings.encoder_factory = &encoder_factory_;
       encoder_config->max_bitrate_bps = 2 * kReconfigureThresholdKbps * 1000;
       encoder_config->video_stream_factory =
           new rtc::RefCountedObject<VideoStreamFactory>();
@@ -770,6 +772,7 @@ TEST_F(CallPerfTest, MAYBE_KeepsHighBitrateWhenReconfiguringSender) {
     uint32_t last_set_bitrate_kbps_;
     VideoSendStream* send_stream_;
     test::FrameGeneratorCapturer* frame_generator_;
+    test::EncoderProxyFactory encoder_factory_;
     VideoEncoderConfig encoder_config_;
   } test;
 
diff --git a/call/video_send_stream.cc b/call/video_send_stream.cc
index 8fccd32c77..ec701d0c7b 100644
--- a/call/video_send_stream.cc
+++ b/call/video_send_stream.cc
@@ -93,7 +93,6 @@ std::string VideoSendStream::Config::EncoderSettings::ToString() const {
   rtc::SimpleStringBuilder ss(buf);
   ss << "{encoder_factory: "
      << (encoder_factory ? "(VideoEncoderFactory)" : "(nullptr)");
-  ss << ", encoder: " << (encoder ? "(VideoEncoder)" : "nullptr");
   ss << '}';
   return ss.str();
 }
diff --git a/call/video_send_stream.h b/call/video_send_stream.h
index 0019a95c65..cdb948395f 100644
--- a/call/video_send_stream.h
+++ b/call/video_send_stream.h
@@ -113,18 +113,8 @@ class VideoSendStream {
 
     struct EncoderSettings {
       EncoderSettings() = default;
-      explicit EncoderSettings(VideoEncoder* encoder) : encoder(encoder) {}
       std::string ToString() const;
 
-      // TODO(sophiechang): Delete this field when no one is using internal
-      // sources anymore.
-      bool internal_source = false;
-
-      // Allow 100% encoder utilization. Used for HW encoders where CPU isn't
-      // expected to be the limiting factor, but a chip could be running at
-      // 30fps (for example) exactly.
-      bool full_overuse_time = false;
-
       // Enables the new method to estimate the cpu load from encoding, used for
       // cpu adaptation.
       bool experiment_cpu_load_estimator = false;
@@ -132,9 +122,8 @@ class VideoSendStream {
       // Ownership stays with WebrtcVideoEngine (delegated from PeerConnection).
       VideoEncoderFactory* encoder_factory = nullptr;
 
-      // TODO(nisse): Delete, let VideoStreamEncoder create the encoder.
-      // Uninitialized VideoEncoder instance to be used for encoding. Will be
-      // initialized from inside the VideoSendStream.
+      // TODO(nisse): Unused! But kept temporarily to transition downstream
+      // projects.
       VideoEncoder* encoder = nullptr;
     } encoder_settings;