Support Opus Ambisonics playback

content/renderer/media/audio_renderer_mixer_manager_unittest.cc

Index: content/renderer/media/audio_renderer_mixer_manager_unittest.cc
diff --git a/content/renderer/media/audio_renderer_mixer_manager_unittest.cc b/content/renderer/media/audio_renderer_mixer_manager_unittest.cc
index 8ef3738fd959ee138571669bb9d87c96a912096d..52f7255d36259a33f8850610530b609e1a3fd337 100644
--- a/content/renderer/media/audio_renderer_mixer_manager_unittest.cc
+++ b/content/renderer/media/audio_renderer_mixer_manager_unittest.cc
@@ -32,6 +32,8 @@ const int kHardwareSampleRate = 44100;
 const int kHardwareBufferSize = 128;
 const media::ChannelLayout kChannelLayout = media::CHANNEL_LAYOUT_STEREO;
 const media::ChannelLayout kAnotherChannelLayout = media::CHANNEL_LAYOUT_2_1;
+const media::ChannelLayout kDiscreteChannelLayout =
+    media::CHANNEL_LAYOUT_DISCRETE;
 const char* const kDefaultDeviceId =
     media::AudioDeviceDescription::kDefaultDeviceId;
 const char kAnotherDeviceId[] = "another-device-id";
@@ -176,13 +178,13 @@ class AudioRendererMixerManagerTest : public testing::Test {
 // Verify GetMixer() and ReturnMixer() both work as expected; particularly with
 // respect to the explicit ref counting done.
 TEST_F(AudioRendererMixerManagerTest, GetReturnMixer) {
-  // Since we're testing two different sets of parameters, we expect
-  // AudioRendererMixerManager to call Start and Stop on our mock twice.
-  EXPECT_CALL(*mock_sink_.get(), Start()).Times(2);
-  EXPECT_CALL(*mock_sink_.get(), Stop()).Times(2);
+  // Since we're testing three different sets of parameters, we expect
+  // AudioRendererMixerManager to call Start and Stop on our mock three times.
+  EXPECT_CALL(*mock_sink_.get(), Start()).Times(3);
+  EXPECT_CALL(*mock_sink_.get(), Stop()).Times(3);
 
-  // We expect 2 mixers to be created; each of them should release the sink.
-  EXPECT_CALL(*this, ReleaseSinkPtr(mock_sink_.get())).Times(2);
+  // We expect 3 mixers to be created; each of them should release the sink.
+  EXPECT_CALL(*this, ReleaseSinkPtr(mock_sink_.get())).Times(3);
 
   // There should be no mixers outstanding to start with.
   EXPECT_EQ(0, mixer_count());
@@ -224,6 +226,23 @@ TEST_F(AudioRendererMixerManagerTest, GetReturnMixer) {
   EXPECT_EQ(1, mixer_count());
   ReturnMixer(mixer2);
   EXPECT_EQ(0, mixer_count());
+
+  // An input with CHANNEL_LAYOUT_DISCRETE should yield a mixer that defaults
+  // to the hardware channel layout.
+  media::AudioParameters params3(AudioParameters::AUDIO_PCM_LINEAR,
+                                 kDiscreteChannelLayout, kSampleRate * 2,
+                                 kBitsPerChannel, kBufferSize * 2);
+  media::AudioRendererMixer* mixer3 =
+      GetMixer(kRenderFrameId, params3, AudioLatency::LATENCY_PLAYBACK,
+               kDefaultDeviceId, kSecurityOrigin, nullptr);
+  ASSERT_TRUE(mixer3);
+  EXPECT_EQ(1, mixer_count());
+  EXPECT_EQ(mock_sink_->GetOutputDeviceInfo().output_params().channel_layout(),
+            mixer3->GetOutputParamsForTesting().channel_layout());
+
+  // Return the final mixer.
+  ReturnMixer(mixer3);
+  EXPECT_EQ(0, mixer_count());
 }
 
 // Verify GetMixer() correctly deduplicates mixer with irrelevant AudioParameter