Reland "Reland "Default enable WebRTC-SendSideBwe-WithOverhead.""

This is a reland of 1dbe30c7e895c7eb4da51c968a7a8897f25ad7e6

Original change's description:
> Reland "Default enable WebRTC-SendSideBwe-WithOverhead."
>
> This is a reland of 87c1950841c3f5e465e1663cc922717ce191e192
>
> Original change's description:
> > Default enable WebRTC-SendSideBwe-WithOverhead.
> >
> > Bug: webrtc:6762
> > Change-Id: I18ace06a33b3b60d5a19796d4769f70cd977d604
> > Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/188801
> > Commit-Queue: Jakob Ivarsson <jakobi@webrtc.org>
> > Reviewed-by: Stefan Holmer <stefan@webrtc.org>
> > Reviewed-by: Ali Tofigh <alito@webrtc.org>
> > Cr-Commit-Position: refs/heads/master@{#32472}
>
> Bug: webrtc:6762
> Change-Id: Icf096a8755d29600a13bd08b1f22f5a79de21e90
> Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/190143
> Reviewed-by: Ali Tofigh <alito@webrtc.org>
> Reviewed-by: Stefan Holmer <stefan@webrtc.org>
> Commit-Queue: Jakob Ivarsson <jakobi@webrtc.org>
> Cr-Commit-Position: refs/heads/master@{#32492}

Bug: webrtc:6762
Change-Id: I6d79894a213fc42d2338409e7513247725881b1a
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/191221
Reviewed-by: Stefan Holmer <stefan@webrtc.org>
Reviewed-by: Ali Tofigh <alito@webrtc.org>
Commit-Queue: Jakob Ivarsson <jakobi@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#32534}

call/call_perf_tests.cc

diff --git a/call/call_perf_tests.cc b/call/call_perf_tests.cc
index 7ddf547..aa8894e 100644
--- a/call/call_perf_tests.cc
+++ b/call/call_perf_tests.cc
@@ -731,6 +731,11 @@
   static const uint32_t kInitialBitrateKbps = 400;
   static const uint32_t kReconfigureThresholdKbps = 600;
 
+  // We get lower bitrate than expected by this test if the following field
+  // trial is enabled.
+  test::ScopedFieldTrials field_trials(
+      "WebRTC-SendSideBwe-WithOverhead/Disabled/");
+
   class VideoStreamFactory
       : public VideoEncoderConfig::VideoStreamFactoryInterface {
    public:

call/rtp_transport_controller_send.cc

diff --git a/call/rtp_transport_controller_send.cc b/call/rtp_transport_controller_send.cc
index 63bb937..f5adae6 100644
--- a/call/rtp_transport_controller_send.cc
+++ b/call/rtp_transport_controller_send.cc
@@ -64,6 +64,11 @@
   return absl::StartsWith(trials->Lookup(key), "Enabled");
 }
 
+bool IsDisabled(const WebRtcKeyValueConfig* trials, absl::string_view key) {
+  RTC_DCHECK(trials != nullptr);
+  return absl::StartsWith(trials->Lookup(key), "Disabled");
+}
+
 bool IsRelayed(const rtc::NetworkRoute& route) {
   return route.local.uses_turn() || route.remote.uses_turn();
 }
@@ -111,7 +116,7 @@
       reset_feedback_on_route_change_(
           !IsEnabled(trials, "WebRTC-Bwe-NoFeedbackReset")),
       send_side_bwe_with_overhead_(
-          IsEnabled(trials, "WebRTC-SendSideBwe-WithOverhead")),
+          !IsDisabled(trials, "WebRTC-SendSideBwe-WithOverhead")),
       add_pacing_to_cwin_(
           IsEnabled(trials, "WebRTC-AddPacingToCongestionWindowPushback")),
       relay_bandwidth_cap_("relay_cap", DataRate::PlusInfinity()),

call/rtp_video_sender.cc

diff --git a/call/rtp_video_sender.cc b/call/rtp_video_sender.cc
index fd71248..9dad424 100644
--- a/call/rtp_video_sender.cc
+++ b/call/rtp_video_sender.cc
@@ -327,9 +327,9 @@
     FrameEncryptorInterface* frame_encryptor,
     const CryptoOptions& crypto_options,
     rtc::scoped_refptr<FrameTransformerInterface> frame_transformer)
-    : send_side_bwe_with_overhead_(absl::StartsWith(
+    : send_side_bwe_with_overhead_(!absl::StartsWith(
           field_trials_.Lookup("WebRTC-SendSideBwe-WithOverhead"),
-          "Enabled")),
+          "Disabled")),
       has_packet_feedback_(TransportSeqNumExtensionConfigured(rtp_config)),
       active_(false),
       module_process_thread_(nullptr),