Add support of overriding network simulation in video quality tests.

Add ability to provide custom implementation of
NetworkSimulatedInterface for sender and receiver network in
VideoQualityTestFixtureInterface, passing them to the factory method.
Also unite this mechanism with FecControllerFactoryInterface injection.


Bug: webrtc:9630
Change-Id: I79259113e0fc00d933b73ca299afa836a4cd19d2
Reviewed-on: https://webrtc-review.googlesource.com/96280
Commit-Queue: Artem Titov <titovartem@webrtc.org>
Reviewed-by: Patrik Höglund <phoglund@webrtc.org>
Reviewed-by: Erik Språng <sprang@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#24476}

api/test/create_video_quality_test_fixture.cc

@@ -26,7 +26,16 @@ CreateVideoQualityTestFixture() {
 std::unique_ptr<VideoQualityTestFixtureInterface>
 CreateVideoQualityTestFixture(
     std::unique_ptr<FecControllerFactoryInterface> fec_controller_factory) {
-  return absl::make_unique<VideoQualityTest>(std::move(fec_controller_factory));
+  auto components = absl::make_unique<
+      VideoQualityTestFixtureInterface::InjectionComponents>();
+  components->fec_controller_factory = std::move(fec_controller_factory);
+  return absl::make_unique<VideoQualityTest>(std::move(components));
+}
+
+std::unique_ptr<VideoQualityTestFixtureInterface> CreateVideoQualityTestFixture(
+    std::unique_ptr<VideoQualityTestFixtureInterface::InjectionComponents>
+        components) {
+  return absl::make_unique<VideoQualityTest>(std::move(components));
 }
 
 }  // namespace webrtc

api/test/create_video_quality_test_fixture.h

@@ -24,6 +24,9 @@ std::unique_ptr<VideoQualityTestFixtureInterface>
 CreateVideoQualityTestFixture(
     std::unique_ptr<FecControllerFactoryInterface> fec_controller_factory);
 
-}
+std::unique_ptr<VideoQualityTestFixtureInterface> CreateVideoQualityTestFixture(
+    std::unique_ptr<VideoQualityTestFixtureInterface::InjectionComponents>
+        components);
+}  // namespace webrtc
 
 #endif  // API_TEST_CREATE_VIDEO_QUALITY_TEST_FIXTURE_H_

api/test/video_quality_test_fixture.h

@@ -84,8 +84,10 @@ class VideoQualityTestFixtureInterface {
     // it is just configuration, that will be passed to default implementation
     // of simulation layer.
     DefaultNetworkSimulationConfig pipe;
-    // Config for default simulation implementation. May be nullopt in that
-    // case, a default config will be used.
+    // Config for default simulation implementation. Must be nullopt if
+    // `sender_network` and `receiver_network` in InjectionComponents are
+    // non-null. May be nullopt even if `sender_network` and `receiver_network`
+    // are null; in that case, a default config will be used.
     absl::optional<DefaultNetworkSimulationConfig> config;
     struct SS {                          // Spatial scalability.
       std::vector<VideoStream> streams;  // If empty, one stream is assumed.
@@ -105,6 +107,21 @@ class VideoQualityTestFixtureInterface {
     } logging;
   };
 
+  // Contains objects, that will be injected on different layers of test
+  // framework to override the behavior of system parts.
+  struct InjectionComponents {
+    InjectionComponents();
+    ~InjectionComponents();
+
+    // Simulations of sender and receiver networks. They must either both be
+    // null (in which case `config` from Params is used), or both be non-null
+    // (in which case `config` from Params must be nullopt).
+    std::unique_ptr<NetworkSimulationInterface> sender_network;
+    std::unique_ptr<NetworkSimulationInterface> receiver_network;
+
+    std::unique_ptr<FecControllerFactoryInterface> fec_controller_factory;
+  };
+
   virtual ~VideoQualityTestFixtureInterface() = default;
 
   virtual void RunWithAnalyzer(const Params& params) = 0;