When a track is added/removed directly to MediaStream notify observer->OnRenegotionNeeded

webrtc/pc/peerconnectioninterface_unittest.cc

Index: webrtc/pc/peerconnectioninterface_unittest.cc
diff --git a/webrtc/pc/peerconnectioninterface_unittest.cc b/webrtc/pc/peerconnectioninterface_unittest.cc
index c10324a94b7a5772733cd473a939226c074981d2..f380d3ba46502a8c884d5715c14f57fea1d6e5c9 100644
--- a/webrtc/pc/peerconnectioninterface_unittest.cc
+++ b/webrtc/pc/peerconnectioninterface_unittest.cc
@@ -3702,3 +3702,37 @@ TEST(RTCConfigurationTest, ComparisonOperators) {
       PeerConnectionInterface::RTCConfigurationType::kAggressive);
   EXPECT_NE(a, h);
 }
+
+// This test ensures OnRenegotiationNeeded is called when we add track with
+// MediaStream -> AddTrack in the same way it is called when we add track with
+// PeerConnection -> AddTrack.
+// The test can be removed once addStream is rewritten in terms of addTrack
+// https://bugs.chromium.org/p/webrtc/issues/detail?id=7815
+TEST_F(PeerConnectionInterfaceTest, MediaStreamAddTrackRemoveTrackRenegotiate) {
+  CreatePeerConnectionWithoutDtls();
+  rtc::scoped_refptr<MediaStreamInterface> stream(
+      pc_factory_->CreateLocalMediaStream(kStreamLabel1));
+  pc_->AddStream(stream);
+  rtc::scoped_refptr<AudioTrackInterface> audio_track(
+      pc_factory_->CreateAudioTrack("audio_track", nullptr));
+  rtc::scoped_refptr<VideoTrackInterface> video_track(
+      pc_factory_->CreateVideoTrack(
+          "video_track", pc_factory_->CreateVideoSource(
+              std::unique_ptr<cricket::VideoCapturer>(
+                  new cricket::FakeVideoCapturer()))));
+  stream->AddTrack(audio_track);
+  EXPECT_TRUE_WAIT(observer_.renegotiation_needed_, kTimeout);
+  observer_.renegotiation_needed_ = false;
+
+  stream->AddTrack(video_track);
+  EXPECT_TRUE_WAIT(observer_.renegotiation_needed_, kTimeout);
+  observer_.renegotiation_needed_ = false;
+
+  stream->RemoveTrack(audio_track);
+  EXPECT_TRUE_WAIT(observer_.renegotiation_needed_, kTimeout);
+  observer_.renegotiation_needed_ = false;
+
+  stream->RemoveTrack(video_track);
+  EXPECT_TRUE_WAIT(observer_.renegotiation_needed_, kTimeout);
+  observer_.renegotiation_needed_ = false;
+}