Revert "Fix target bitrate RTCP messages behavior for SVC streams"

This reverts commit ab65d8aab5fe63619033371fca1ce2711c2c2137.

Reason for revert: Fails video_engine_tests ExtendedReportsEndToEndTest.TestExtendedReportsCanSignalZeroTargetBitrate
https://ci.chromium.org/p/webrtc/builders/ci/Linux%20MSan/18366

Original change's description:
> Fix target bitrate RTCP messages behavior for SVC streams
>
> Before this CL for SVC streams (e.g VP9) still 3 separate RTP_RTCP senders
> were created. The RTCP target bitrate messages were treated as simulcast
> and were split and send for each separate spatial layer in a separate SSRC.
>
> To fix that an svc flag is now wired to VideoSendStream config
> and filled based on the encoder config in WebrtcVideoEngine. This flag is
> used to differentiate between simulcast and SVC mode in RtpVideoSender.
>
> Bug: webrtc:10485
> Change-Id: Ifa01d12a7d4f01fcbe448ad11e0cc39ab2d1df55
> Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/129929
> Commit-Queue: Ilya Nikolaevskiy <ilnik@webrtc.org>
> Reviewed-by: Niels Moller <nisse@webrtc.org>
> Reviewed-by: Erik Språng <sprang@webrtc.org>
> Cr-Commit-Position: refs/heads/master@{#27345}

TBR=ilnik@webrtc.org,nisse@webrtc.org,sprang@webrtc.org

Change-Id: I184f87289d9dccc67de165038d76a5690158a3b5
No-Tree-Checks: True
No-Try: True
Bug: webrtc:10485
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/130467
Commit-Queue: Oleh Prypin <oprypin@webrtc.org>
Reviewed-by: Oleh Prypin <oprypin@webrtc.org>
Reviewed-by: Ilya Nikolaevskiy <ilnik@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#27355}
diff --git a/call/rtp_transport_controller_send.cc b/call/rtp_transport_controller_send.cc
index 2816550..ab95907 100644
--- a/call/rtp_transport_controller_send.cc
+++ b/call/rtp_transport_controller_send.cc
@@ -104,14 +104,13 @@
     const RtpConfig& rtp_config,
     int rtcp_report_interval_ms,
     Transport* send_transport,
-    bool is_svc,
     const RtpSenderObservers& observers,
     RtcEventLog* event_log,
     std::unique_ptr<FecController> fec_controller,
     const RtpSenderFrameEncryptionConfig& frame_encryption_config) {
   video_rtp_senders_.push_back(absl::make_unique<RtpVideoSender>(
       clock_, suspended_ssrcs, states, rtp_config, rtcp_report_interval_ms,
-      send_transport, is_svc, observers,
+      send_transport, observers,
       // TODO(holmer): Remove this circular dependency by injecting
       // the parts of RtpTransportControllerSendInterface that are really used.
       this, event_log, &retransmission_rate_limiter_, std::move(fec_controller),
diff --git a/call/rtp_transport_controller_send.h b/call/rtp_transport_controller_send.h
index 44135e4..c8a9f2c 100644
--- a/call/rtp_transport_controller_send.h
+++ b/call/rtp_transport_controller_send.h
@@ -60,7 +60,6 @@
       const RtpConfig& rtp_config,
       int rtcp_report_interval_ms,
       Transport* send_transport,
-      bool is_svc,
       const RtpSenderObservers& observers,
       RtcEventLog* event_log,
       std::unique_ptr<FecController> fec_controller,
diff --git a/call/rtp_transport_controller_send_interface.h b/call/rtp_transport_controller_send_interface.h
index 32862d8..d564035 100644
--- a/call/rtp_transport_controller_send_interface.h
+++ b/call/rtp_transport_controller_send_interface.h
@@ -104,7 +104,6 @@
       const RtpConfig& rtp_config,
       int rtcp_report_interval_ms,
       Transport* send_transport,
-      bool is_svc,
       const RtpSenderObservers& observers,
       RtcEventLog* event_log,
       std::unique_ptr<FecController> fec_controller,
diff --git a/call/rtp_video_sender.cc b/call/rtp_video_sender.cc
index 748196d..87edf10 100644
--- a/call/rtp_video_sender.cc
+++ b/call/rtp_video_sender.cc
@@ -212,7 +212,6 @@
     const RtpConfig& rtp_config,
     int rtcp_report_interval_ms,
     Transport* send_transport,
-    bool is_svc,
     const RtpSenderObservers& observers,
     RtpTransportControllerSendInterface* transport,
     RtcEventLog* event_log,
@@ -254,8 +253,7 @@
       overhead_bytes_per_packet_(0),
       encoder_target_rate_bps_(0),
       frame_counts_(rtp_config.ssrcs.size()),
-      frame_count_observer_(observers.frame_count_observer),
-      is_svc_(is_svc) {
+      frame_count_observer_(observers.frame_count_observer) {
   RTC_DCHECK_EQ(rtp_config.ssrcs.size(), rtp_streams_.size());
   module_process_thread_checker_.DetachFromThread();
   // SSRCs are assumed to be sorted in the same order as |rtp_modules|.
@@ -450,7 +448,7 @@
     const VideoBitrateAllocation& bitrate) {
   rtc::CritScope lock(&crit_);
   if (IsActive()) {
-    if (rtp_streams_.size() == 1 || is_svc_) {
+    if (rtp_streams_.size() == 1) {
       // If spatial scalability is enabled, it is covered by a single stream.
       rtp_streams_[0].rtp_rtcp->SetVideoBitrateAllocation(bitrate);
     } else {
diff --git a/call/rtp_video_sender.h b/call/rtp_video_sender.h
index 5c0094f..d50cb7c 100644
--- a/call/rtp_video_sender.h
+++ b/call/rtp_video_sender.h
@@ -76,7 +76,6 @@
       const RtpConfig& rtp_config,
       int rtcp_report_interval_ms,
       Transport* send_transport,
-      bool is_svc,
       const RtpSenderObservers& observers,
       RtpTransportControllerSendInterface* transport,
       RtcEventLog* event_log,
@@ -191,8 +190,6 @@
   std::vector<FrameCounts> frame_counts_ RTC_GUARDED_BY(crit_);
   FrameCountObserver* const frame_count_observer_;
 
-  const bool is_svc_;
-
   RTC_DISALLOW_COPY_AND_ASSIGN(RtpVideoSender);
 };
 
diff --git a/call/rtp_video_sender_unittest.cc b/call/rtp_video_sender_unittest.cc
index e51e72a..1a1dd9b 100644
--- a/call/rtp_video_sender_unittest.cc
+++ b/call/rtp_video_sender_unittest.cc
@@ -99,7 +99,7 @@
     std::map<uint32_t, RtpState> suspended_ssrcs;
     router_ = absl::make_unique<RtpVideoSender>(
         &clock_, suspended_ssrcs, suspended_payload_states, config_.rtp,
-        config_.rtcp_report_interval_ms, &transport_, config_.is_svc,
+        config_.rtcp_report_interval_ms, &transport_,
         CreateObservers(&call_stats_, &encoder_feedback_, &stats_proxy_,
                         &stats_proxy_, &stats_proxy_, frame_count_observer,
                         &stats_proxy_, &stats_proxy_, &send_delay_stats_),
diff --git a/call/test/mock_rtp_transport_controller_send.h b/call/test/mock_rtp_transport_controller_send.h
index af44008..b5a0a85 100644
--- a/call/test/mock_rtp_transport_controller_send.h
+++ b/call/test/mock_rtp_transport_controller_send.h
@@ -32,14 +32,13 @@
 class MockRtpTransportControllerSend
     : public RtpTransportControllerSendInterface {
  public:
-  MOCK_METHOD10(
+  MOCK_METHOD9(
       CreateRtpVideoSender,
       RtpVideoSenderInterface*(std::map<uint32_t, RtpState>,
                                const std::map<uint32_t, RtpPayloadState>&,
                                const RtpConfig&,
                                int rtcp_report_interval_ms,
                                Transport*,
-                               bool,
                                const RtpSenderObservers&,
                                RtcEventLog*,
                                std::unique_ptr<FecController>,
diff --git a/call/video_send_stream.h b/call/video_send_stream.h
index e4f96d7..5daec19 100644
--- a/call/video_send_stream.h
+++ b/call/video_send_stream.h
@@ -151,10 +151,6 @@
     // Per PeerConnection cryptography options.
     CryptoOptions crypto_options;
 
-    // Forces spatial scalability to be implemented via spatial layers
-    // instead of simulcast.
-    bool is_svc;
-
    private:
     // Access to the copy constructor is private to force use of the Copy()
     // method for those exceptional cases where we do use it.
diff --git a/media/engine/webrtc_video_engine.cc b/media/engine/webrtc_video_engine.cc
index 7b75840..acbc36f 100644
--- a/media/engine/webrtc_video_engine.cc
+++ b/media/engine/webrtc_video_engine.cc
@@ -2302,7 +2302,6 @@
                            "payload type the set codec. Ignoring RTX.";
     config.rtp.rtx.ssrcs.clear();
   }
-  config.is_svc = parameters_.encoder_config.number_of_streams == 1;
   stream_ = call_->CreateVideoSendStream(std::move(config),
                                          parameters_.encoder_config.Copy());
 
diff --git a/video/video_quality_test.cc b/video/video_quality_test.cc
index b8cf006..23c703e 100644
--- a/video/video_quality_test.cc
+++ b/video/video_quality_test.cc
@@ -762,9 +762,6 @@
     video_send_configs_[video_idx].suspend_below_min_bitrate =
         params_.video[video_idx].suspend_below_min_bitrate;
 
-    video_send_configs_[video_idx].is_svc =
-        params_.ss[video_idx].streams.size() == 1;
-
     video_encoder_configs_[video_idx].number_of_streams =
         params_.ss[video_idx].streams.size();
     video_encoder_configs_[video_idx].max_bitrate_bps = 0;
diff --git a/video/video_send_stream_impl.cc b/video/video_send_stream_impl.cc
index 33ee854..ae905df 100644
--- a/video/video_send_stream_impl.cc
+++ b/video/video_send_stream_impl.cc
@@ -236,7 +236,6 @@
           config_->rtp,
           config_->rtcp_report_interval_ms,
           config_->send_transport,
-          config_->is_svc,
           CreateObservers(call_stats,
                           &encoder_feedback_,
                           stats_proxy_,
diff --git a/video/video_send_stream_impl_unittest.cc b/video/video_send_stream_impl_unittest.cc
index 47a1e66..e8eab84 100644
--- a/video/video_send_stream_impl_unittest.cc
+++ b/video/video_send_stream_impl_unittest.cc
@@ -96,7 +96,7 @@
     EXPECT_CALL(transport_controller_, packet_router())
         .WillRepeatedly(Return(&packet_router_));
     EXPECT_CALL(transport_controller_,
-                CreateRtpVideoSender(_, _, _, _, _, _, _, _, _, _))
+                CreateRtpVideoSender(_, _, _, _, _, _, _, _, _))
         .WillRepeatedly(Return(&rtp_video_sender_));
     EXPECT_CALL(rtp_video_sender_, SetActive(_))
         .WillRepeatedly(testing::Invoke(