From 10ea11841098bd62a0ded7c6084debd92b9f227c Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Erik=20Spr=C3=A5ng?= <sprang@webrtc.org>
Date: Mon, 28 Sep 2020 18:04:46 +0200
Subject: [PATCH] Default-enables WebRTC-DeferredFecGeneration.
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Bug: webrtc:11340
Change-Id: I9575fcf2ac12ce9b71b27f32deeb7870a1dff64b
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/185814
Commit-Queue: Erik Språng <sprang@webrtc.org>
Reviewed-by: Sebastian Jansson <srte@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#32232}
---
 call/rtp_video_sender.cc                     |  6 +++---
 modules/rtp_rtcp/source/rtp_sender_egress.cc | 20 ++++++++++++--------
 2 files changed, 15 insertions(+), 11 deletions(-)

diff --git a/call/rtp_video_sender.cc b/call/rtp_video_sender.cc
index b2ae0352d8..caee744e76 100644
--- a/call/rtp_video_sender.cc
+++ b/call/rtp_video_sender.cc
@@ -341,9 +341,9 @@ RtpVideoSender::RtpVideoSender(
           field_trials_.Lookup("WebRTC-UseEarlyLossDetection"),
           "Disabled")),
       has_packet_feedback_(TransportSeqNumExtensionConfigured(rtp_config)),
-      use_deferred_fec_(
-          absl::StartsWith(field_trials_.Lookup("WebRTC-DeferredFecGeneration"),
-                           "Enabled")),
+      use_deferred_fec_(!absl::StartsWith(
+          field_trials_.Lookup("WebRTC-DeferredFecGeneration"),
+          "Disabled")),
       active_(false),
       module_process_thread_(nullptr),
       suspended_ssrcs_(std::move(suspended_ssrcs)),
diff --git a/modules/rtp_rtcp/source/rtp_sender_egress.cc b/modules/rtp_rtcp/source/rtp_sender_egress.cc
index c89b9e42ce..dbd96e461e 100644
--- a/modules/rtp_rtcp/source/rtp_sender_egress.cc
+++ b/modules/rtp_rtcp/source/rtp_sender_egress.cc
@@ -30,11 +30,12 @@ constexpr size_t kRtpSequenceNumberMapMaxEntries = 1 << 13;
 constexpr TimeDelta kUpdateInterval =
     TimeDelta::Millis(kBitrateStatisticsWindowMs);
 
-bool IsEnabled(absl::string_view name,
-               const WebRtcKeyValueConfig* field_trials) {
+bool IsTrialSetTo(const WebRtcKeyValueConfig* field_trials,
+                  absl::string_view name,
+                  absl::string_view value) {
   FieldTrialBasedConfig default_trials;
   auto& trials = field_trials ? *field_trials : default_trials;
-  return absl::StartsWith(trials.Lookup(name), "Enabled");
+  return absl::StartsWith(trials.Lookup(name), value);
 }
 }  // namespace
 
@@ -89,7 +90,9 @@ RtpSenderEgress::RtpSenderEgress(const RtpRtcpInterface::Configuration& config,
                                          : absl::nullopt),
       populate_network2_timestamp_(config.populate_network2_timestamp),
       send_side_bwe_with_overhead_(
-          IsEnabled("WebRTC-SendSideBwe-WithOverhead", config.field_trials)),
+          IsTrialSetTo(config.field_trials,
+                       "WebRTC-SendSideBwe-WithOverhead",
+                       "Enabled")),
       clock_(config.clock),
       packet_history_(packet_history),
       transport_(config.outgoing_transport),
@@ -98,10 +101,11 @@ RtpSenderEgress::RtpSenderEgress(const RtpRtcpInterface::Configuration& config,
       is_audio_(config.audio),
 #endif
       need_rtp_packet_infos_(config.need_rtp_packet_infos),
-      fec_generator_(
-          IsEnabled("WebRTC-DeferredFecGeneration", config.field_trials)
-              ? config.fec_generator
-              : nullptr),
+      fec_generator_(!IsTrialSetTo(config.field_trials,
+                                   "WebRTC-DeferredFecGeneration",
+                                   "Disabled")
+                         ? config.fec_generator
+                         : nullptr),
       transport_feedback_observer_(config.transport_feedback_callback),
       send_side_delay_observer_(config.send_side_delay_observer),
       send_packet_observer_(config.send_packet_observer),