device/bluetooth: Implement Unregister() of BlueotoothAudioSinkChromeOS and disconnection-related c…

device/bluetooth/bluetooth_audio_sink_chromeos_unittest.cc

Index: device/bluetooth/bluetooth_audio_sink_chromeos_unittest.cc
diff --git a/device/bluetooth/bluetooth_audio_sink_chromeos_unittest.cc b/device/bluetooth/bluetooth_audio_sink_chromeos_unittest.cc
index 9aa727f08b4c862a8e40bf8df65961c8bb2c5b6e..7889e6f2e1618d5a4f3442b02dc9ba0c7833aae5 100644
--- a/device/bluetooth/bluetooth_audio_sink_chromeos_unittest.cc
+++ b/device/bluetooth/bluetooth_audio_sink_chromeos_unittest.cc
@@ -87,6 +87,7 @@ class BluetoothAudioSinkChromeOSTest : public testing::Test {
   void TearDown() override {
     callback_count_ = 0;
     error_callback_count_ = 0;
+    observer_.reset();
 
     // The adapter should outlive audio sink.
     audio_sink_ = nullptr;
@@ -138,8 +139,20 @@ class BluetoothAudioSinkChromeOSTest : public testing::Test {
         base::Bind(&BluetoothAudioSinkChromeOSTest::RegisterErrorCallback,
                    base::Unretained(this)));
 
+    observer_.reset(new TestAudioSinkObserver(audio_sink_));
     EXPECT_EQ(callback_count_, 1);
     EXPECT_EQ(error_callback_count_, 0);
+    EXPECT_EQ(observer_->state_changed_count_, 0);
+    EXPECT_EQ(observer_->volume_changed_count_, 0);
+  }
+
+  void GetFakeMediaEndpoint() {
+    BluetoothAudioSinkChromeOS* audio_sink_chromeos =
+        static_cast<BluetoothAudioSinkChromeOS*>(audio_sink_.get());
+    ASSERT_NE(audio_sink_chromeos, nullptr);
+
+    media_endpoint_ = static_cast<FakeBluetoothMediaEndpointServiceProvider*>(
+        audio_sink_chromeos->GetEndpointServiceProvider());
   }
 
   // Called whenever RegisterAudioSink is completed successfully.
@@ -181,6 +194,8 @@ class BluetoothAudioSinkChromeOSTest : public testing::Test {
 
   base::MessageLoop message_loop_;
 
+  FakeBluetoothMediaEndpointServiceProvider* media_endpoint_;
+  scoped_ptr<TestAudioSinkObserver> observer_;
   scoped_refptr<BluetoothAdapter> adapter_;
   scoped_refptr<BluetoothAudioSink> audio_sink_;
 
@@ -192,11 +207,6 @@ class BluetoothAudioSinkChromeOSTest : public testing::Test {
 
 TEST_F(BluetoothAudioSinkChromeOSTest, RegisterSucceeded) {
   GetAudioSink();
-
-  // Adds an observer for |audio_sink_|.
-  TestAudioSinkObserver observer(audio_sink_);
-  EXPECT_EQ(observer.state_changed_count_, 0);
-  EXPECT_EQ(observer.volume_changed_count_, 0);
 }
 
 TEST_F(BluetoothAudioSinkChromeOSTest, RegisterFailedWithInvalidOptions) {
@@ -231,22 +241,12 @@ TEST_F(BluetoothAudioSinkChromeOSTest, RegisterFailedWithInvalidOptions) {
 
 TEST_F(BluetoothAudioSinkChromeOSTest, SelectConfiguration) {
   GetAudioSink();
-
-  // Adds an observer for |audio_sink_|.
-  TestAudioSinkObserver observer(audio_sink_);
-  EXPECT_EQ(observer.state_changed_count_, 0);
-  EXPECT_EQ(observer.volume_changed_count_, 0);
+  GetFakeMediaEndpoint();
+  ASSERT_NE(media_endpoint_, nullptr);
 
   // Simulates calling SelectConfiguration on the media endpoint object owned by
   // |audio_sink_| with some fake capabilities.
-  BluetoothAudioSinkChromeOS* audio_sink_chromeos =
-      static_cast<BluetoothAudioSinkChromeOS*>(audio_sink_.get());
-  FakeBluetoothMediaEndpointServiceProvider* media_endpoint =
-      static_cast<FakeBluetoothMediaEndpointServiceProvider*>(
-          audio_sink_chromeos->GetEndpointServiceProvider());
-  ASSERT_NE(media_endpoint, nullptr);
-
-  media_endpoint->SelectConfiguration(
+  media_endpoint_->SelectConfiguration(
       std::vector<uint8_t>({0x21, 0x15, 0x33, 0x2C}),
       base::Bind(&BluetoothAudioSinkChromeOSTest::SelectConfigurationCallback,
                  base::Unretained(this)));
@@ -254,81 +254,57 @@ TEST_F(BluetoothAudioSinkChromeOSTest, SelectConfiguration) {
   EXPECT_EQ(audio_sink_->GetState(), BluetoothAudioSink::STATE_DISCONNECTED);
   EXPECT_EQ(callback_count_, 2);
   EXPECT_EQ(error_callback_count_, 0);
-  EXPECT_EQ(observer.state_changed_count_, 0);
-  EXPECT_EQ(observer.volume_changed_count_, 0);
+  EXPECT_EQ(observer_->state_changed_count_, 0);
+  EXPECT_EQ(observer_->volume_changed_count_, 0);
 }
 
 TEST_F(BluetoothAudioSinkChromeOSTest, SetConfiguration) {
   GetAudioSink();
-
-  // Adds an observer for |audio_sink_|.
-  TestAudioSinkObserver observer(audio_sink_);
-  EXPECT_EQ(observer.state_changed_count_, 0);
-  EXPECT_EQ(observer.volume_changed_count_, 0);
+  GetFakeMediaEndpoint();
+  ASSERT_NE(media_endpoint_, nullptr);
 
   // Simulates calling SetConfiguration on the media endpoint object owned by
   // |audio_sink_| with a fake transport path and a
   // Delegate::TransportProperties structure.
-  BluetoothAudioSinkChromeOS* audio_sink_chromeos =
-      static_cast<BluetoothAudioSinkChromeOS*>(audio_sink_.get());
-  FakeBluetoothMediaEndpointServiceProvider* media_endpoint =
-      static_cast<FakeBluetoothMediaEndpointServiceProvider*>(
-          audio_sink_chromeos->GetEndpointServiceProvider());
-  ASSERT_NE(media_endpoint, nullptr);
-
-  media_endpoint->SetConfiguration(
+  media_endpoint_->SetConfiguration(
       ObjectPath(FakeBluetoothMediaTransportClient::kTransportPath),
       properties_);
 
   EXPECT_EQ(audio_sink_->GetState(), BluetoothAudioSink::STATE_IDLE);
   EXPECT_EQ(callback_count_, 1);
   EXPECT_EQ(error_callback_count_, 0);
-  EXPECT_EQ(observer.state_changed_count_, 1);
-  EXPECT_EQ(observer.volume_changed_count_, 1);
+  EXPECT_EQ(observer_->state_changed_count_, 1);
+  EXPECT_EQ(observer_->volume_changed_count_, 1);
 }
 
 TEST_F(BluetoothAudioSinkChromeOSTest, SetConfigurationWithUnexpectedState) {
   GetAudioSink();
-
-  // Adds an observer for |audio_sink_|.
-  TestAudioSinkObserver observer(audio_sink_);
-  EXPECT_EQ(observer.state_changed_count_, 0);
-  EXPECT_EQ(observer.volume_changed_count_, 0);
-
-  // Simulates calling SetConfiguration on the media endpoint object owned by
-  // |audio_sink_| with a fake transport path and a
-  // Delegate::TransportProperties structure.
-  BluetoothAudioSinkChromeOS* audio_sink_chromeos =
-      static_cast<BluetoothAudioSinkChromeOS*>(audio_sink_.get());
-  FakeBluetoothMediaEndpointServiceProvider* media_endpoint =
-      static_cast<FakeBluetoothMediaEndpointServiceProvider*>(
-          audio_sink_chromeos->GetEndpointServiceProvider());
-  ASSERT_NE(media_endpoint, nullptr);
+  GetFakeMediaEndpoint();
+  ASSERT_NE(media_endpoint_, nullptr);
 
   // Set state of Delegate::TransportProperties with an unexpected value.
   properties_.state = "active";
 
-  media_endpoint->SetConfiguration(
+  media_endpoint_->SetConfiguration(
       ObjectPath(FakeBluetoothMediaTransportClient::kTransportPath),
       properties_);
 
   EXPECT_EQ(audio_sink_->GetState(), BluetoothAudioSink::STATE_DISCONNECTED);
   EXPECT_EQ(callback_count_, 1);
   EXPECT_EQ(error_callback_count_, 0);
-  EXPECT_EQ(observer.state_changed_count_, 0);
-  EXPECT_EQ(observer.volume_changed_count_, 0);
+  EXPECT_EQ(observer_->state_changed_count_, 0);
+  EXPECT_EQ(observer_->volume_changed_count_, 0);
 }
 
-// Checks if the observer is notified while the media object is
-// removed(invisible). Once the media object is removed, the audio sink is no
-// longer valid.
-TEST_F(BluetoothAudioSinkChromeOSTest, ObserverNotifiedWhenMediaRemoved) {
+// TODO(mcchou): Adds test on media-removed events for STATE_PENDING and
+// STATE_ACTIVE.
+// Checks if the observer is notified on media-removed event when the state of
+// |audio_sink_| is STATE_DISCONNECTED. Once the media object is removed, the
+// audio sink is no longer valid.
+TEST_F(BluetoothAudioSinkChromeOSTest, MediaRemovedDuringDisconnectedState) {
   GetAudioSink();
-
-  // Adds an observer for |audio_sink_|.
-  TestAudioSinkObserver observer(audio_sink_);
-  EXPECT_EQ(observer.state_changed_count_, 0);
-  EXPECT_EQ(observer.volume_changed_count_, 0);
+  GetFakeMediaEndpoint();
+  ASSERT_NE(media_endpoint_, nullptr);
 
   // Gets the media object and makes it invisible to see if the state of the
   // audio sink changes accordingly.
@@ -336,46 +312,69 @@ TEST_F(BluetoothAudioSinkChromeOSTest, ObserverNotifiedWhenMediaRemoved) {
       DBusThreadManager::Get()->GetBluetoothMediaClient());
   media->SetVisible(false);
 
-  BluetoothAudioSinkChromeOS* audio_sink_chromeos =
-      static_cast<BluetoothAudioSinkChromeOS*>(audio_sink_.get());
-  FakeBluetoothMediaEndpointServiceProvider* media_endpoint =
-      static_cast<FakeBluetoothMediaEndpointServiceProvider*>(
-          audio_sink_chromeos->GetEndpointServiceProvider());
+  GetFakeMediaEndpoint();
 
   EXPECT_EQ(audio_sink_->GetState(), BluetoothAudioSink::STATE_INVALID);
-  EXPECT_EQ(media_endpoint, nullptr);
+  EXPECT_EQ(media_endpoint_, nullptr);
+  EXPECT_EQ(observer_->state_changed_count_, 1);
+  EXPECT_EQ(observer_->volume_changed_count_, 0);
 }
 
-// Checks if the observer is notified while the media transport is
-// removed(invisible). Once the media transport object is removed, the audio
-// sink is disconnected.
-TEST_F(BluetoothAudioSinkChromeOSTest, ObserverNotifiedWhenTransportRemoved) {
+// Checks if the observer is  notified on media-removed event when the state of
+// |audio_sink_| is STATE_IDLE. Once the media object is removed, the audio sink
+// is no longer valid.
+TEST_F(BluetoothAudioSinkChromeOSTest, MediaRemovedDuringIdleState) {
   GetAudioSink();
+  GetFakeMediaEndpoint();
+  ASSERT_NE(media_endpoint_, nullptr);
 
-  // Adds an observer for |audio_sink_|.
-  TestAudioSinkObserver observer(audio_sink_);
-  EXPECT_EQ(observer.state_changed_count_, 0);
-  EXPECT_EQ(observer.volume_changed_count_, 0);
+  media_endpoint_->SetConfiguration(
+      ObjectPath(FakeBluetoothMediaTransportClient::kTransportPath),
+      properties_);
 
-  // Simulates calling SetConfiguration on the media endpoint object owned by
-  // |audio_sink_| with a fake transport path and a
-  // Delegate::TransportProperties structure.
-  BluetoothAudioSinkChromeOS* audio_sink_chromeos =
-      static_cast<BluetoothAudioSinkChromeOS*>(audio_sink_.get());
-  FakeBluetoothMediaEndpointServiceProvider* media_endpoint =
-      static_cast<FakeBluetoothMediaEndpointServiceProvider*>(
-          audio_sink_chromeos->GetEndpointServiceProvider());
-  ASSERT_NE(media_endpoint, nullptr);
-
-  media_endpoint->SetConfiguration(
+  EXPECT_EQ(audio_sink_->GetState(), BluetoothAudioSink::STATE_IDLE);
+  EXPECT_EQ(callback_count_, 1);
+  EXPECT_EQ(error_callback_count_, 0);
+  EXPECT_EQ(observer_->state_changed_count_, 1);
+  EXPECT_EQ(observer_->volume_changed_count_, 1);
+
+  // Gets the media object and makes it invisible to see if the state of the
+  // audio sink changes accordingly.
+  FakeBluetoothMediaClient* media = static_cast<FakeBluetoothMediaClient*>(
+      DBusThreadManager::Get()->GetBluetoothMediaClient());
+  media->SetVisible(false);
+
+  GetFakeMediaEndpoint();
+
+  EXPECT_EQ(audio_sink_->GetState(), BluetoothAudioSink::STATE_INVALID);
+  EXPECT_EQ(media_endpoint_, nullptr);
+  // The state becomes disconnted and then invalid, since the removal of
+  // transport object should happend before media becomes invisible.
+  // State: STATE_IDLE -> STATE_DISCONNECTED -> STATE_INVALID
+  EXPECT_EQ(observer_->state_changed_count_, 3);
+  EXPECT_EQ(observer_->volume_changed_count_, 2);
+}
+
+// TODO(mcchou): Add tests on media-removed event for STATE_PENDING and
+// STATE_ACTIVE.
+
+// Checks if the observer is notified on transport-removed event when the state
+// of |audio_sink_| is STATE_IDEL. Once the media transport object is removed,
+// the audio sink is disconnected.
+TEST_F(BluetoothAudioSinkChromeOSTest, TransportRemovedDuringIdleState) {
+  GetAudioSink();
+  GetFakeMediaEndpoint();
+  ASSERT_NE(media_endpoint_, nullptr);
+
+  media_endpoint_->SetConfiguration(
       ObjectPath(FakeBluetoothMediaTransportClient::kTransportPath),
       properties_);
 
   EXPECT_EQ(audio_sink_->GetState(), BluetoothAudioSink::STATE_IDLE);
   EXPECT_EQ(callback_count_, 1);
   EXPECT_EQ(error_callback_count_, 0);
-  EXPECT_EQ(observer.state_changed_count_, 1);
-  EXPECT_EQ(observer.volume_changed_count_, 1);
+  EXPECT_EQ(observer_->state_changed_count_, 1);
+  EXPECT_EQ(observer_->volume_changed_count_, 1);
 
   // Gets the media transport object and makes it invalid to see if the state
   // of the audio sink changes accordingly.
@@ -383,9 +382,202 @@ TEST_F(BluetoothAudioSinkChromeOSTest, ObserverNotifiedWhenTransportRemoved) {
       static_cast<FakeBluetoothMediaTransportClient*>(
           DBusThreadManager::Get()->GetBluetoothMediaTransportClient());
 
-  transport->SetValid(media_endpoint->object_path(), false);
+  transport->SetValid(media_endpoint_->object_path(), false);
+
+  EXPECT_EQ(audio_sink_->GetState(), BluetoothAudioSink::STATE_DISCONNECTED);
+  EXPECT_NE(media_endpoint_, nullptr);
+  EXPECT_EQ(observer_->state_changed_count_, 2);
+  EXPECT_EQ(observer_->volume_changed_count_, 2);
+}
+
+// TODO(mcchou): Add tests on transport-removed event for STATE_PENDING and
+// STATE_ACTIVE.
+
+TEST_F(BluetoothAudioSinkChromeOSTest,
+       AdapterPoweredChangedDuringDisconnectedState) {
+  GetAudioSink();
+
+  adapter_->SetPowered(
+      false,
+      base::Bind(&BluetoothAudioSinkChromeOSTest::Callback,
+                 base::Unretained(this)),
+      base::Bind(&BluetoothAudioSinkChromeOSTest::ErrorCallback,
+                 base::Unretained(this)));
+
+  EXPECT_TRUE(adapter_->IsPresent());
+  EXPECT_FALSE(adapter_->IsPowered());
+  EXPECT_EQ(audio_sink_->GetState(), BluetoothAudioSink::STATE_DISCONNECTED);
+  EXPECT_EQ(callback_count_, 2);
+  EXPECT_EQ(error_callback_count_, 0);
+  EXPECT_EQ(observer_->state_changed_count_, 0);
+  EXPECT_EQ(observer_->volume_changed_count_, 0);
+
+  adapter_->SetPowered(
+      true,
+      base::Bind(&BluetoothAudioSinkChromeOSTest::Callback,
+                 base::Unretained(this)),
+      base::Bind(&BluetoothAudioSinkChromeOSTest::ErrorCallback,
+                 base::Unretained(this)));
+
+  EXPECT_TRUE(adapter_->IsPresent());
+  EXPECT_TRUE(adapter_->IsPowered());
+  EXPECT_EQ(audio_sink_->GetState(), BluetoothAudioSink::STATE_DISCONNECTED);
+  EXPECT_EQ(callback_count_, 3);
+  EXPECT_EQ(error_callback_count_, 0);
+  EXPECT_EQ(observer_->state_changed_count_, 0);
+  EXPECT_EQ(observer_->volume_changed_count_, 0);
+}
+
+TEST_F(BluetoothAudioSinkChromeOSTest, AdapterPoweredChangedDuringIdleState) {
+  GetAudioSink();
+  GetFakeMediaEndpoint();
+  ASSERT_NE(media_endpoint_, nullptr);
+
+  media_endpoint_->SetConfiguration(
+      ObjectPath(FakeBluetoothMediaTransportClient::kTransportPath),
+      properties_);
+
+  EXPECT_EQ(audio_sink_->GetState(), BluetoothAudioSink::STATE_IDLE);
+  EXPECT_EQ(callback_count_, 1);
+  EXPECT_EQ(error_callback_count_, 0);
+  EXPECT_EQ(observer_->state_changed_count_, 1);
+  EXPECT_EQ(observer_->volume_changed_count_, 1);
+
+  adapter_->SetPowered(
+      false,
+      base::Bind(&BluetoothAudioSinkChromeOSTest::Callback,
+                 base::Unretained(this)),
+      base::Bind(&BluetoothAudioSinkChromeOSTest::ErrorCallback,
+                 base::Unretained(this)));
+  GetFakeMediaEndpoint();
+
+  EXPECT_TRUE(adapter_->IsPresent());
+  EXPECT_FALSE(adapter_->IsPowered());
+  EXPECT_NE(media_endpoint_, nullptr);
+
+  EXPECT_EQ(audio_sink_->GetState(), BluetoothAudioSink::STATE_DISCONNECTED);
+  EXPECT_EQ(callback_count_, 2);
+  EXPECT_EQ(error_callback_count_, 0);
+  EXPECT_EQ(observer_->state_changed_count_, 2);
+  EXPECT_EQ(observer_->volume_changed_count_, 2);
+}
+
+// TODO(mcchou): Add tests on AdapterPoweredChanged event for STATE_PENDING and
+// STATE_ACTIVE.
+
+TEST_F(BluetoothAudioSinkChromeOSTest, ClearConfiguration) {
+  GetAudioSink();
+  GetFakeMediaEndpoint();
+  ASSERT_NE(media_endpoint_, nullptr);
+
+  media_endpoint_->SetConfiguration(
+      ObjectPath(FakeBluetoothMediaTransportClient::kTransportPath),
+      properties_);
+
+  EXPECT_EQ(audio_sink_->GetState(), BluetoothAudioSink::STATE_IDLE);
+  EXPECT_EQ(callback_count_, 1);
+  EXPECT_EQ(error_callback_count_, 0);
+  EXPECT_EQ(observer_->state_changed_count_, 1);
+  EXPECT_EQ(observer_->volume_changed_count_, 1);
+
+  // Simulates calling ClearConfiguration on the media endpoint object with the
+  // transport path.
+  media_endpoint_->ClearConfiguration(
+      ObjectPath(FakeBluetoothMediaTransportClient::kTransportPath));
+
   EXPECT_EQ(audio_sink_->GetState(), BluetoothAudioSink::STATE_DISCONNECTED);
-  EXPECT_NE(media_endpoint, nullptr);
+  EXPECT_EQ(observer_->state_changed_count_, 2);
+  EXPECT_EQ(observer_->volume_changed_count_, 2);
+}
+
+TEST_F(BluetoothAudioSinkChromeOSTest, ClearConfigurationWithIrrelevantPath) {
+  GetAudioSink();
+  GetFakeMediaEndpoint();
+  ASSERT_NE(media_endpoint_, nullptr);
+
+  media_endpoint_->SetConfiguration(
+      ObjectPath(FakeBluetoothMediaTransportClient::kTransportPath),
+      properties_);
+
+  EXPECT_EQ(audio_sink_->GetState(), BluetoothAudioSink::STATE_IDLE);
+  EXPECT_EQ(callback_count_, 1);
+  EXPECT_EQ(error_callback_count_, 0);
+  EXPECT_EQ(observer_->state_changed_count_, 1);
+  EXPECT_EQ(observer_->volume_changed_count_, 1);
+
+  // Simulates calling ClearConfiguration on the media endpoint object with an
+  // irrelevant transport path.
+  media_endpoint_->ClearConfiguration(ObjectPath("IrrelevantPath"));
+
+  EXPECT_EQ(audio_sink_->GetState(), BluetoothAudioSink::STATE_IDLE);
+  EXPECT_EQ(observer_->state_changed_count_, 1);
+  EXPECT_EQ(observer_->volume_changed_count_, 1);
+}
+
+TEST_F(BluetoothAudioSinkChromeOSTest, EndpointReleased) {

[Miao, 2015/02/23 21:04:25]

Removed this test. This can be included in UnregisterAudioSinkDuringIdleState
test.
Released() will be called in the following cases:
(1) UnregisterEndpoint gets called.
(2) Set the media object to be invisible.

+  GetAudioSink();
+  GetFakeMediaEndpoint();
+  ASSERT_NE(media_endpoint_, nullptr);
+
+  media_endpoint_->SetConfiguration(
+      ObjectPath(FakeBluetoothMediaTransportClient::kTransportPath),
+      properties_);
+
+  EXPECT_EQ(audio_sink_->GetState(), BluetoothAudioSink::STATE_IDLE);
+  EXPECT_EQ(callback_count_, 1);
+  EXPECT_EQ(error_callback_count_, 0);
+  EXPECT_EQ(observer_->state_changed_count_, 1);
+  EXPECT_EQ(observer_->volume_changed_count_, 1);
+
+  // Simulates calling Release on the media endpoint object.
+  media_endpoint_->Released();
+
+  GetFakeMediaEndpoint();
+
+  EXPECT_EQ(audio_sink_->GetState(), BluetoothAudioSink::STATE_INVALID);
+  EXPECT_EQ(media_endpoint_, nullptr);
+  EXPECT_EQ(observer_->state_changed_count_, 2);
+  EXPECT_EQ(observer_->volume_changed_count_, 2);
+}
+
+TEST_F(BluetoothAudioSinkChromeOSTest, UnregisterAudioSinkDuringIdleState) {
+  GetAudioSink();
+  GetFakeMediaEndpoint();
+  ASSERT_NE(media_endpoint_, nullptr);
+
+  media_endpoint_->SelectConfiguration(
+      std::vector<uint8_t>({0x21, 0x15, 0x33, 0x2C}),
+      base::Bind(&BluetoothAudioSinkChromeOSTest::SelectConfigurationCallback,
+                 base::Unretained(this)));
+
+  EXPECT_EQ(audio_sink_->GetState(), BluetoothAudioSink::STATE_DISCONNECTED);
+  EXPECT_EQ(callback_count_, 2);
+  EXPECT_EQ(error_callback_count_, 0);
+  EXPECT_EQ(observer_->state_changed_count_, 0);
+  EXPECT_EQ(observer_->volume_changed_count_, 0);
+
+  media_endpoint_->SetConfiguration(
+      ObjectPath(FakeBluetoothMediaTransportClient::kTransportPath),
+      properties_);
+
+  EXPECT_EQ(audio_sink_->GetState(), BluetoothAudioSink::STATE_IDLE);
+  EXPECT_EQ(callback_count_, 2);
+  EXPECT_EQ(error_callback_count_, 0);
+  EXPECT_EQ(observer_->state_changed_count_, 1);
+  EXPECT_EQ(observer_->volume_changed_count_, 1);
+
+  audio_sink_->Unregister(base::Bind(&BluetoothAudioSinkChromeOSTest::Callback,
+                                    base::Unretained(this)));
+
+  EXPECT_EQ(audio_sink_->GetState(), BluetoothAudioSink::STATE_INVALID);
+  EXPECT_EQ(callback_count_, 3);
+  EXPECT_EQ(error_callback_count_, 0);
+
+  // The state becomes disconnted and then invalid, since the removal of
+  // transport object should happend before the unregistration of endpoint.
+  // State: STATE_IDLE -> STATE_DISCONNECTED -> STATE_INVALID
+  EXPECT_EQ(observer_->state_changed_count_, 3);
+  EXPECT_EQ(observer_->volume_changed_count_, 2);
 }
 
 }  // namespace chromeos