Adding cbr support for Opus

webrtc/modules/audio_coding/codecs/opus/audio_encoder_opus_unittest.cc

Index: webrtc/modules/audio_coding/codecs/opus/audio_encoder_opus_unittest.cc
diff --git a/webrtc/modules/audio_coding/codecs/opus/audio_encoder_opus_unittest.cc b/webrtc/modules/audio_coding/codecs/opus/audio_encoder_opus_unittest.cc
index 1d4fc2e7813c9c3b2eee1bc6596be2ace20e47f6..0e134699081446289de3d7e65157cf26ff4f7ed8 100644
--- a/webrtc/modules/audio_coding/codecs/opus/audio_encoder_opus_unittest.cc
+++ b/webrtc/modules/audio_coding/codecs/opus/audio_encoder_opus_unittest.cc
@@ -182,6 +182,18 @@ TEST(AudioEncoderOpusTest, ToggleDtx) {
   EXPECT_TRUE(states.encoder->SetDtx(false));
 }
 
+TEST(AudioEncoderOpusTest, ToggleCbr) {
+  auto states = CreateCodec(2);
+  // Enable CBR
+  EXPECT_TRUE(states.encoder->SetCbr(true));
+  // Verify that CBR is on.
+  EXPECT_TRUE(states.encoder->GetCbr());
+  // Turn off CBR.
+  EXPECT_TRUE(states.encoder->SetCbr(false));
+  // Verify that CBR is off.
+  EXPECT_FALSE(states.encoder->GetCbr());
+}
+
 TEST(AudioEncoderOpusTest,
      OnReceivedUplinkBandwidthWithoutAudioNetworkAdaptor) {
   auto states = CreateCodec(1);