Pass FecControllerOverride to Vp8FrameBufferControllerFactory::Create

Previously, FecControllerOverride was passed to
Vp8FrameBufferController::SetFecControllerOverride. Passing to
the factory is a more elegant way, since it's only used when
the controller is constructed.

TBR=kwiberg@webrtc.org

Bug: webrtc:10769
Change-Id: Iae599889e7ca9003e3200c2911239cbb763ee65a
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/144380
Reviewed-by: Erik Språng <sprang@webrtc.org>
Commit-Queue: Elad Alon <eladalon@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#28443}
diff --git a/api/BUILD.gn b/api/BUILD.gn
index 77246bc..2ca55c7 100644
--- a/api/BUILD.gn
+++ b/api/BUILD.gn
@@ -649,6 +649,17 @@
     ]
   }
 
+  rtc_source_set("mock_fec_controller_override") {
+    testonly = true
+    sources = [
+      "test/mock_fec_controller_override.h",
+    ]
+    deps = [
+      ":fec_controller_api",
+      "../test:test_support",
+    ]
+  }
+
   rtc_source_set("mock_frame_encryptor") {
     testonly = true
     sources = [
diff --git a/api/test/mock_fec_controller_override.h b/api/test/mock_fec_controller_override.h
new file mode 100644
index 0000000..a7ec836
--- /dev/null
+++ b/api/test/mock_fec_controller_override.h
@@ -0,0 +1,28 @@
+/*
+ *  Copyright 2019 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+#ifndef API_TEST_MOCK_FEC_CONTROLLER_OVERRIDE_H_
+#define API_TEST_MOCK_FEC_CONTROLLER_OVERRIDE_H_
+
+#include "api/fec_controller_override.h"
+#include "test/gmock.h"
+
+namespace webrtc {
+
+class MockFecControllerOverride : public FecControllerOverride {
+ public:
+  ~MockFecControllerOverride() override = default;
+
+  MOCK_METHOD1(SetFecAllowed, void(bool fec_allowed));
+};
+
+}  // namespace webrtc
+
+#endif  // API_TEST_MOCK_FEC_CONTROLLER_OVERRIDE_H_
diff --git a/api/video_codecs/BUILD.gn b/api/video_codecs/BUILD.gn
index f53ae7b..894d23f 100644
--- a/api/video_codecs/BUILD.gn
+++ b/api/video_codecs/BUILD.gn
@@ -120,6 +120,7 @@
 
   deps = [
     ":video_codecs_api",
+    "../:fec_controller_api",
     "../../modules/video_coding:video_coding_utility",
     "../../modules/video_coding:webrtc_vp8_temporal_layers",
     "../../rtc_base:checks",
diff --git a/api/video_codecs/vp8_frame_buffer_controller.h b/api/video_codecs/vp8_frame_buffer_controller.h
index 94e08a9..f304413 100644
--- a/api/video_codecs/vp8_frame_buffer_controller.h
+++ b/api/video_codecs/vp8_frame_buffer_controller.h
@@ -106,13 +106,6 @@
   // The limits are suggestion-only; the controller is allowed to exceed them.
   virtual void SetQpLimits(size_t stream_index, int min_qp, int max_qp) = 0;
 
-  // Set a FecControllerOverride, through which the bandwidth allocation
-  // decisions made by FecController may be overridden.
-  // TODO(bugs.webrtc.org/10769): Update downstream projects, then make
-  // this pure-virtual.
-  virtual void SetFecControllerOverride(
-      FecControllerOverride* fec_controller_override) {}
-
   // Number of streamed controlled by |this|.
   virtual size_t StreamCount() const = 0;
 
@@ -188,9 +181,24 @@
   virtual std::unique_ptr<Vp8FrameBufferControllerFactory> Clone() const = 0;
 
   // Create a Vp8FrameBufferController instance.
+  // TODO(bugs.webrtc.org/10769): Update downstream projects, then remove
+  // version without |fec_controller_override| and make the other version
+  // pure-virtual.
+  // (In theory, if neither version is overridden, stack overflow would occur.
+  // In practice, all subclasses override at least one version, and following
+  // the update of downstream projects, only one pure-virtual version will
+  // remain.)
   virtual std::unique_ptr<Vp8FrameBufferController> Create(
       const VideoCodec& codec,
-      const VideoEncoder::Settings& settings) = 0;
+      const VideoEncoder::Settings& settings) {
+    return Create(codec, settings, nullptr);
+  }
+  virtual std::unique_ptr<Vp8FrameBufferController> Create(
+      const VideoCodec& codec,
+      const VideoEncoder::Settings& settings,
+      FecControllerOverride* fec_controller_override) {
+    return Create(codec, settings);
+  }
 };
 
 }  // namespace webrtc
diff --git a/api/video_codecs/vp8_temporal_layers.cc b/api/video_codecs/vp8_temporal_layers.cc
index b29cf65..dd75c61 100644
--- a/api/video_codecs/vp8_temporal_layers.cc
+++ b/api/video_codecs/vp8_temporal_layers.cc
@@ -18,7 +18,8 @@
 namespace webrtc {
 
 Vp8TemporalLayers::Vp8TemporalLayers(
-    std::vector<std::unique_ptr<Vp8FrameBufferController>>&& controllers)
+    std::vector<std::unique_ptr<Vp8FrameBufferController>>&& controllers,
+    FecControllerOverride* fec_controller_override)
     : controllers_(std::move(controllers)) {
   RTC_DCHECK(!controllers_.empty());
   RTC_DCHECK(absl::c_none_of(
@@ -26,6 +27,9 @@
       [](const std::unique_ptr<Vp8FrameBufferController>& controller) {
         return controller.get() == nullptr;
       }));
+  if (fec_controller_override) {
+    fec_controller_override->SetFecAllowed(true);
+  }
 }
 
 void Vp8TemporalLayers::SetQpLimits(size_t stream_index,
@@ -35,11 +39,6 @@
   return controllers_[stream_index]->SetQpLimits(0, min_qp, max_qp);
 }
 
-void Vp8TemporalLayers::SetFecControllerOverride(
-    FecControllerOverride* fec_controller_override) {
-  // Ignore.
-}
-
 size_t Vp8TemporalLayers::StreamCount() const {
   return controllers_.size();
 }
diff --git a/api/video_codecs/vp8_temporal_layers.h b/api/video_codecs/vp8_temporal_layers.h
index efd013e..2ffe6ea 100644
--- a/api/video_codecs/vp8_temporal_layers.h
+++ b/api/video_codecs/vp8_temporal_layers.h
@@ -32,15 +32,13 @@
 // realize a temporal layer structure.
 class Vp8TemporalLayers final : public Vp8FrameBufferController {
  public:
-  explicit Vp8TemporalLayers(
-      std::vector<std::unique_ptr<Vp8FrameBufferController>>&& controllers);
+  Vp8TemporalLayers(
+      std::vector<std::unique_ptr<Vp8FrameBufferController>>&& controllers,
+      FecControllerOverride* fec_controller_override);
   ~Vp8TemporalLayers() override = default;
 
   void SetQpLimits(size_t stream_index, int min_qp, int max_qp) override;
 
-  void SetFecControllerOverride(
-      FecControllerOverride* fec_controller_override) override;
-
   size_t StreamCount() const override;
 
   bool SupportsEncoderFrameDropping(size_t stream_index) const override;
diff --git a/api/video_codecs/vp8_temporal_layers_factory.cc b/api/video_codecs/vp8_temporal_layers_factory.cc
index 1a77323..f7d991c 100644
--- a/api/video_codecs/vp8_temporal_layers_factory.cc
+++ b/api/video_codecs/vp8_temporal_layers_factory.cc
@@ -15,6 +15,7 @@
 #include <vector>
 
 #include "absl/memory/memory.h"
+#include "api/fec_controller_override.h"
 #include "modules/video_coding/codecs/vp8/default_temporal_layers.h"
 #include "modules/video_coding/codecs/vp8/screenshare_layers.h"
 #include "modules/video_coding/utility/simulcast_utility.h"
@@ -25,6 +26,13 @@
 std::unique_ptr<Vp8FrameBufferController> Vp8TemporalLayersFactory::Create(
     const VideoCodec& codec,
     const VideoEncoder::Settings& settings) {
+  return Create(codec, settings, nullptr);
+}
+
+std::unique_ptr<Vp8FrameBufferController> Vp8TemporalLayersFactory::Create(
+    const VideoCodec& codec,
+    const VideoEncoder::Settings& settings,
+    FecControllerOverride* fec_controller_override) {
   std::vector<std::unique_ptr<Vp8FrameBufferController>> controllers;
   const int num_streams = SimulcastUtility::NumberOfSimulcastStreams(codec);
   RTC_DCHECK_GE(num_streams, 1);
@@ -44,7 +52,8 @@
     }
   }
 
-  return absl::make_unique<Vp8TemporalLayers>(std::move(controllers));
+  return absl::make_unique<Vp8TemporalLayers>(std::move(controllers),
+                                              fec_controller_override);
 }
 
 std::unique_ptr<Vp8FrameBufferControllerFactory>
diff --git a/api/video_codecs/vp8_temporal_layers_factory.h b/api/video_codecs/vp8_temporal_layers_factory.h
index 747580f..082bfe2 100644
--- a/api/video_codecs/vp8_temporal_layers_factory.h
+++ b/api/video_codecs/vp8_temporal_layers_factory.h
@@ -23,9 +23,15 @@
 
   std::unique_ptr<Vp8FrameBufferControllerFactory> Clone() const override;
 
+  // TODO(bugs.webrtc.org/10769): Update downstream projects, then remove.
   std::unique_ptr<Vp8FrameBufferController> Create(
       const VideoCodec& codec,
       const VideoEncoder::Settings& settings) override;
+
+  std::unique_ptr<Vp8FrameBufferController> Create(
+      const VideoCodec& codec,
+      const VideoEncoder::Settings& settings,
+      FecControllerOverride* fec_controller_override) override;
 };
 
 }  // namespace webrtc