device/bluetooth: Add I/O watcher for audio data retrieval triggered by state change.

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 ee6cf2ab8c1197b95468cec0fad9d883a36c7e41..b415e73d1b6707c2a9de47b183716f43af5e957e 100644
--- a/device/bluetooth/bluetooth_audio_sink_chromeos_unittest.cc
+++ b/device/bluetooth/bluetooth_audio_sink_chromeos_unittest.cc
@@ -34,6 +34,7 @@ class TestAudioSinkObserver : public BluetoothAudioSink::Observer {
   explicit TestAudioSinkObserver(scoped_refptr<BluetoothAudioSink> audio_sink)
       : state_changed_count_(0),
         volume_changed_count_(0),
+        total_read_(0),
         state_(audio_sink->GetState()),
         audio_sink_(audio_sink) {
     audio_sink_->AddObserver(this);
@@ -44,6 +45,9 @@ class TestAudioSinkObserver : public BluetoothAudioSink::Observer {
   void BluetoothAudioSinkStateChanged(
       BluetoothAudioSink* audio_sink,
       BluetoothAudioSink::State state) override {
+    if (state == BluetoothAudioSink::STATE_IDLE)
+      total_read_ = 0;
+
     ++state_changed_count_;
   }
 
@@ -52,8 +56,19 @@ class TestAudioSinkObserver : public BluetoothAudioSink::Observer {
     ++volume_changed_count_;
   }
 
+  void BluetoothAudioSinkDataAvailable(BluetoothAudioSink* audio_sink,
+                                       char* data,
+                                       size_t size) override {
+    total_read_ += size;
+    data_.clear();
+    data_.insert(data_.begin(), data, data + size);
+  }
+
   int state_changed_count_;
   int volume_changed_count_;
+  int data_available_count_;
+  size_t total_read_;
+  std::vector<char> data_;
   BluetoothAudioSink::State state_;
 
  private:
@@ -68,6 +83,11 @@ class BluetoothAudioSinkChromeOSTest : public testing::Test {
     callback_count_ = 0;
     error_callback_count_ = 0;
 
+    fake_media_ = static_cast<FakeBluetoothMediaClient*>(
+        DBusThreadManager::Get()->GetBluetoothMediaClient());
+    fake_transport_ = static_cast<FakeBluetoothMediaTransportClient*>(
+        DBusThreadManager::Get()->GetBluetoothMediaTransportClient());
+
     // Initiates Delegate::TransportProperties with default values.
     properties_.device =
         ObjectPath(FakeBluetoothMediaTransportClient::kTransportDevicePath);
@@ -81,11 +101,6 @@ class BluetoothAudioSinkChromeOSTest : public testing::Test {
     properties_.volume.reset(
         new uint16_t(FakeBluetoothMediaTransportClient::kTransportVolume));
 
-    media_ = static_cast<FakeBluetoothMediaClient*>(
-        DBusThreadManager::Get()->GetBluetoothMediaClient());
-    transport_ = static_cast<FakeBluetoothMediaTransportClient*>(
-        DBusThreadManager::Get()->GetBluetoothMediaTransportClient());
-
     GetAdapter();
   }
 
@@ -94,7 +109,7 @@ class BluetoothAudioSinkChromeOSTest : public testing::Test {
     error_callback_count_ = 0;
     observer_.reset();
 
-    media_->SetVisible(true);
+    fake_media_->SetVisible(true);
 
     // The adapter should outlive audio sink.
     audio_sink_ = nullptr;
@@ -172,7 +187,7 @@ class BluetoothAudioSinkChromeOSTest : public testing::Test {
 
     GetFakeMediaEndpoint();
     ASSERT_NE(media_endpoint_, nullptr);
-    media_->SetEndpointRegistered(media_endpoint_, true);
+    fake_media_->SetEndpointRegistered(media_endpoint_, true);
 
     ASSERT_NE(audio_sink_.get(), nullptr);
     ASSERT_EQ(audio_sink_->GetState(), BluetoothAudioSink::STATE_DISCONNECTED);
@@ -211,10 +226,10 @@ class BluetoothAudioSinkChromeOSTest : public testing::Test {
   int callback_count_;
   int error_callback_count_;
 
-  base::MessageLoop message_loop_;
+  base::MessageLoopForIO message_loop_;
 
-  FakeBluetoothMediaClient* media_;
-  FakeBluetoothMediaTransportClient* transport_;
+  FakeBluetoothMediaClient* fake_media_;
+  FakeBluetoothMediaTransportClient* fake_transport_;
   FakeBluetoothMediaEndpointServiceProvider* media_endpoint_;
   scoped_ptr<TestAudioSinkObserver> observer_;
   scoped_refptr<BluetoothAdapter> adapter_;
@@ -295,7 +310,7 @@ TEST_F(BluetoothAudioSinkChromeOSTest, SetConfiguration) {
   // |audio_sink_| with a fake transport path and a
   // Delegate::TransportProperties structure.
   media_endpoint_->SetConfiguration(
-      transport_->GetTransportPath(media_endpoint_->object_path()),
+      fake_transport_->GetTransportPath(media_endpoint_->object_path()),
       properties_);
 
   EXPECT_EQ(audio_sink_->GetState(), BluetoothAudioSink::STATE_IDLE);
@@ -323,7 +338,7 @@ TEST_F(BluetoothAudioSinkChromeOSTest, SetConfigurationWithUnexpectedState) {
   properties_.state = "pending";
 
   media_endpoint_->SetConfiguration(
-      transport_->GetTransportPath(media_endpoint_->object_path()),
+      fake_transport_->GetTransportPath(media_endpoint_->object_path()),
       properties_);
 
   EXPECT_EQ(audio_sink_->GetState(), BluetoothAudioSink::STATE_DISCONNECTED);
@@ -333,8 +348,6 @@ TEST_F(BluetoothAudioSinkChromeOSTest, SetConfigurationWithUnexpectedState) {
   EXPECT_EQ(observer_->volume_changed_count_, 0);
 }
 
-// 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.
@@ -343,7 +356,7 @@ TEST_F(BluetoothAudioSinkChromeOSTest, MediaRemovedDuringDisconnectedState) {
 
   // Gets the media object and makes it invisible to see if the state of the
   // audio sink changes accordingly.
-  media_->SetVisible(false);
+  fake_media_->SetVisible(false);
 
   GetFakeMediaEndpoint();
 
@@ -371,7 +384,7 @@ TEST_F(BluetoothAudioSinkChromeOSTest, MediaRemovedDuringIdleState) {
   EXPECT_EQ(observer_->volume_changed_count_, 0);
 
   media_endpoint_->SetConfiguration(
-      transport_->GetTransportPath(media_endpoint_->object_path()),
+      fake_transport_->GetTransportPath(media_endpoint_->object_path()),
       properties_);
 
   EXPECT_EQ(audio_sink_->GetState(), BluetoothAudioSink::STATE_IDLE);
@@ -382,7 +395,7 @@ TEST_F(BluetoothAudioSinkChromeOSTest, MediaRemovedDuringIdleState) {
 
   // Gets the media object and makes it invisible to see if the state of the
   // audio sink changes accordingly.
-  media_->SetVisible(false);
+  fake_media_->SetVisible(false);
 
   GetFakeMediaEndpoint();
 
@@ -396,8 +409,56 @@ TEST_F(BluetoothAudioSinkChromeOSTest, MediaRemovedDuringIdleState) {
   EXPECT_EQ(observer_->volume_changed_count_, 2);
 }
 
-// TODO(mcchou): Add tests on transport-removed event for STATE_PENDING and
-// STATE_ACTIVE.
+TEST_F(BluetoothAudioSinkChromeOSTest, MediaRemovedDuringActiveState) {
+  GetAudioSink();
+
+  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(
+      fake_transport_->GetTransportPath(media_endpoint_->object_path()),
+      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);
+
+  fake_transport_->SetState(media_endpoint_->object_path(), "pending");
+
+  message_loop_.RunUntilIdle();
+
+  // Acquire is called when the state of |audio_sink_| becomes STATE_PENDING,
+  // and Acquire will trigger state change. Therefore, the state will be
+  // STATE_ACTIVE right after STATE_PENDING.
+  // State: STATE_IDLE -> STATE_PENDING -> STATE_ACTIVE
+  EXPECT_EQ(observer_->state_changed_count_, 3);
+
+  // Gets the media object and makes it invisible to see if the state of the
+  // audio sink changes accordingly.
+  fake_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_ACTIVE -> STATE_DISCONNECTED -> STATE_INVALID
+  EXPECT_EQ(observer_->state_changed_count_, 5);
+  EXPECT_EQ(observer_->volume_changed_count_, 2);
+}
+
 // 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.
@@ -416,7 +477,7 @@ TEST_F(BluetoothAudioSinkChromeOSTest, TransportRemovedDuringIdleState) {
   EXPECT_EQ(observer_->volume_changed_count_, 0);
 
   media_endpoint_->SetConfiguration(
-      transport_->GetTransportPath(media_endpoint_->object_path()),
+      fake_transport_->GetTransportPath(media_endpoint_->object_path()),
       properties_);
 
   EXPECT_EQ(audio_sink_->GetState(), BluetoothAudioSink::STATE_IDLE);
@@ -427,7 +488,7 @@ TEST_F(BluetoothAudioSinkChromeOSTest, TransportRemovedDuringIdleState) {
 
   // Makes the transport object invalid to see if the state of the audio sink
   // changes accordingly.
-  transport_->SetValid(media_endpoint_, false);
+  fake_transport_->SetValid(media_endpoint_, false);
 
   EXPECT_EQ(audio_sink_->GetState(), BluetoothAudioSink::STATE_DISCONNECTED);
   EXPECT_NE(media_endpoint_, nullptr);
@@ -435,6 +496,50 @@ TEST_F(BluetoothAudioSinkChromeOSTest, TransportRemovedDuringIdleState) {
   EXPECT_EQ(observer_->volume_changed_count_, 2);
 }
 
+TEST_F(BluetoothAudioSinkChromeOSTest, TransportRemovedDuringActiveState) {
+  GetAudioSink();
+
+  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(
+      fake_transport_->GetTransportPath(media_endpoint_->object_path()),
+      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);
+
+  fake_transport_->SetState(media_endpoint_->object_path(), "pending");
+
+  message_loop_.RunUntilIdle();
+
+  // Acquire is called when the state of |audio_sink_| becomes STATE_PENDING,
+  // and Acquire will trigger state change. Therefore, the state will be
+  // STATE_ACTIVE right after STATE_PENDING.
+  // State: STATE_IDLE -> STATE_PENDING -> STATE_ACTIVE
+  EXPECT_EQ(observer_->state_changed_count_, 3);
+
+  // Makes the transport object invalid to see if the state of the audio sink
+  // changes accordingly.
+  fake_transport_->SetValid(media_endpoint_, false);
+
+  EXPECT_EQ(audio_sink_->GetState(), BluetoothAudioSink::STATE_DISCONNECTED);
+  EXPECT_NE(media_endpoint_, nullptr);
+  EXPECT_EQ(observer_->state_changed_count_, 4);
+  EXPECT_EQ(observer_->volume_changed_count_, 2);
+}
+
 TEST_F(BluetoothAudioSinkChromeOSTest,
        AdapterPoweredChangedDuringDisconnectedState) {
   GetAudioSink();
@@ -485,7 +590,7 @@ TEST_F(BluetoothAudioSinkChromeOSTest, AdapterPoweredChangedDuringIdleState) {
   EXPECT_EQ(observer_->volume_changed_count_, 0);
 
   media_endpoint_->SetConfiguration(
-      transport_->GetTransportPath(media_endpoint_->object_path()),
+      fake_transport_->GetTransportPath(media_endpoint_->object_path()),
       properties_);
 
   EXPECT_EQ(audio_sink_->GetState(), BluetoothAudioSink::STATE_IDLE);
@@ -512,9 +617,6 @@ TEST_F(BluetoothAudioSinkChromeOSTest, AdapterPoweredChangedDuringIdleState) {
   EXPECT_EQ(observer_->volume_changed_count_, 2);
 }
 
-// TODO(mcchou): Add tests on UnregisterAudioSink for STATE_PENDING and
-// STATE_ACTIVE.
-
 TEST_F(BluetoothAudioSinkChromeOSTest,
        UnregisterAudioSinkDuringDisconnectedState) {
   GetAudioSink();
@@ -547,7 +649,7 @@ TEST_F(BluetoothAudioSinkChromeOSTest, UnregisterAudioSinkDuringIdleState) {
   EXPECT_EQ(observer_->volume_changed_count_, 0);
 
   media_endpoint_->SetConfiguration(
-      transport_->GetTransportPath(media_endpoint_->object_path()),
+      fake_transport_->GetTransportPath(media_endpoint_->object_path()),
       properties_);
 
   EXPECT_EQ(audio_sink_->GetState(), BluetoothAudioSink::STATE_IDLE);
@@ -573,6 +675,53 @@ TEST_F(BluetoothAudioSinkChromeOSTest, UnregisterAudioSinkDuringIdleState) {
   EXPECT_EQ(observer_->volume_changed_count_, 2);
 }
 
+TEST_F(BluetoothAudioSinkChromeOSTest, UnregisterAudioSinkDuringActiveState) {
+  GetAudioSink();
+
+  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(
+      fake_transport_->GetTransportPath(media_endpoint_->object_path()),
+      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);
+
+  fake_transport_->SetState(media_endpoint_->object_path(), "pending");
+
+  message_loop_.RunUntilIdle();
+
+  // Acquire is called when the state of |audio_sink_| becomes STATE_PENDING,
+  // and Acquire will trigger state change. Therefore, the state will be
+  // STATE_ACTIVE right after STATE_PENDING.
+  // State: STATE_IDLE -> STATE_PENDING -> STATE_ACTIVE
+  EXPECT_EQ(observer_->state_changed_count_, 3);
+
+  audio_sink_->Unregister(
+      base::Bind(&BluetoothAudioSinkChromeOSTest::Callback,
+                 base::Unretained(this)),
+      base::Bind(&BluetoothAudioSinkChromeOSTest::UnregisterErrorCallback,
+                 base::Unretained(this)));
+
+  EXPECT_EQ(audio_sink_->GetState(), BluetoothAudioSink::STATE_INVALID);
+  EXPECT_EQ(callback_count_, 3);
+  EXPECT_EQ(error_callback_count_, 0);
+  EXPECT_EQ(observer_->state_changed_count_, 5);
+  EXPECT_EQ(observer_->volume_changed_count_, 2);
+}
+
 TEST_F(BluetoothAudioSinkChromeOSTest, StateChanged) {
   GetAudioSink();
 
@@ -588,7 +737,7 @@ TEST_F(BluetoothAudioSinkChromeOSTest, StateChanged) {
   EXPECT_EQ(observer_->volume_changed_count_, 0);
 
   media_endpoint_->SetConfiguration(
-      transport_->GetTransportPath(media_endpoint_->object_path()),
+      fake_transport_->GetTransportPath(media_endpoint_->object_path()),
       properties_);
 
   EXPECT_EQ(audio_sink_->GetState(), BluetoothAudioSink::STATE_IDLE);
@@ -598,10 +747,10 @@ TEST_F(BluetoothAudioSinkChromeOSTest, StateChanged) {
   EXPECT_EQ(observer_->volume_changed_count_, 1);
 
   // Changes the current state of transport to pending.
-  transport_->SetState(media_endpoint_->object_path(), "pending");
+  fake_transport_->SetState(media_endpoint_->object_path(), "pending");
 
   EXPECT_EQ(audio_sink_->GetState(), BluetoothAudioSink::STATE_PENDING);
-  EXPECT_EQ(observer_->state_changed_count_, 2);
+  EXPECT_EQ(observer_->state_changed_count_, 3);
   EXPECT_EQ(observer_->volume_changed_count_, 1);
 }
 
@@ -620,7 +769,7 @@ TEST_F(BluetoothAudioSinkChromeOSTest, VolumeChanged) {
   EXPECT_EQ(observer_->volume_changed_count_, 0);
 
   media_endpoint_->SetConfiguration(
-      transport_->GetTransportPath(media_endpoint_->object_path()),
+      fake_transport_->GetTransportPath(media_endpoint_->object_path()),
       properties_);
 
   EXPECT_EQ(audio_sink_->GetState(), BluetoothAudioSink::STATE_IDLE);
@@ -635,7 +784,7 @@ TEST_F(BluetoothAudioSinkChromeOSTest, VolumeChanged) {
             FakeBluetoothMediaTransportClient::kTransportVolume);
 
   // Changes volume to a valid level.
-  transport_->SetVolume(media_endpoint_->object_path(), 100);
+  fake_transport_->SetVolume(media_endpoint_->object_path(), 100);
 
   EXPECT_EQ(audio_sink_->GetState(), BluetoothAudioSink::STATE_IDLE);
   EXPECT_EQ(observer_->state_changed_count_, 1);
@@ -643,7 +792,7 @@ TEST_F(BluetoothAudioSinkChromeOSTest, VolumeChanged) {
   EXPECT_EQ(audio_sink_->GetVolume(), 100);
 
   // Changes volume to an invalid level.
-  transport_->SetVolume(media_endpoint_->object_path(), 200);
+  fake_transport_->SetVolume(media_endpoint_->object_path(), 200);
 
   EXPECT_EQ(audio_sink_->GetState(), BluetoothAudioSink::STATE_IDLE);
   EXPECT_EQ(observer_->state_changed_count_, 1);
@@ -651,4 +800,144 @@ TEST_F(BluetoothAudioSinkChromeOSTest, VolumeChanged) {
   EXPECT_EQ(audio_sink_->GetVolume(), BluetoothAudioSink::kInvalidVolume);
 }
 
+TEST_F(BluetoothAudioSinkChromeOSTest, AcquireFD) {
+  GetAudioSink();
+
+  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(
+      fake_transport_->GetTransportPath(media_endpoint_->object_path()),
+      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);
+
+  fake_transport_->SetState(media_endpoint_->object_path(), "pending");
+
+  std::vector<char> data_one(16, 0x12);
+  fake_transport_->WriteData(media_endpoint_->object_path(), data_one);
+
+  message_loop_.RunUntilIdle();
+
+  // Acquire is called when the state of |audio_sink_| becomes STATE_PENDING,
+  // and Acquire will trigger state change. Therefore, the state will be
+  // STATE_ACTIVE right after STATE_PENDING.
+  // State: STATE_IDLE -> STATE_PENDING -> STATE_ACTIVE
+  EXPECT_EQ(observer_->state_changed_count_, 3);
+  EXPECT_EQ(observer_->total_read_, data_one.size());
+  EXPECT_EQ(observer_->data_, data_one);
+}
+
+// Tests the case where the remote device pauses and resume audio streaming.
+TEST_F(BluetoothAudioSinkChromeOSTest, PauseAndResume) {
+  GetAudioSink();
+
+  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(
+      fake_transport_->GetTransportPath(media_endpoint_->object_path()),
+      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);
+
+  fake_transport_->SetState(media_endpoint_->object_path(), "pending");
+
+  std::vector<char> data_one(16, 0x12);
+  fake_transport_->WriteData(media_endpoint_->object_path(), data_one);
+
+  message_loop_.RunUntilIdle();
+
+  EXPECT_EQ(observer_->data_, data_one);
+  EXPECT_EQ(observer_->state_changed_count_, 3);
+  EXPECT_EQ(observer_->total_read_, data_one.size());
+
+  // Simulates the situation where the remote device pauses and resume audio
+  // streaming.
+  fake_transport_->SetState(media_endpoint_->object_path(), "idle");
+
+  EXPECT_EQ(audio_sink_->GetState(), BluetoothAudioSink::STATE_IDLE);
+  EXPECT_EQ(observer_->state_changed_count_, 4);
+
+  fake_transport_->SetState(media_endpoint_->object_path(), "pending");
+
+  std::vector<char> data_two(8, 0x10);
+  fake_transport_->WriteData(media_endpoint_->object_path(), data_two);
+
+  message_loop_.RunUntilIdle();
+
+  EXPECT_EQ(observer_->data_, data_two);
+  EXPECT_EQ(observer_->state_changed_count_, 6);
+  EXPECT_EQ(observer_->total_read_, data_two.size());
+}
+
+TEST_F(BluetoothAudioSinkChromeOSTest, ContinuouslyStreaming) {
+  GetAudioSink();
+
+  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(
+      fake_transport_->GetTransportPath(media_endpoint_->object_path()),
+      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);
+
+  fake_transport_->SetState(media_endpoint_->object_path(), "pending");
+
+  std::vector<char> data_one(16, 0x12);
+  fake_transport_->WriteData(media_endpoint_->object_path(), data_one);
+
+  message_loop_.RunUntilIdle();
+
+  EXPECT_EQ(observer_->data_, data_one);
+  EXPECT_EQ(observer_->state_changed_count_, 3);
+  EXPECT_EQ(observer_->total_read_, data_one.size());
+
+  std::vector<char> data_two(8, 0x10);
+  fake_transport_->WriteData(media_endpoint_->object_path(), data_two);
+
+  message_loop_.RunUntilIdle();
+
+  EXPECT_EQ(observer_->data_, data_two);
+  EXPECT_EQ(observer_->state_changed_count_, 3);
+  EXPECT_EQ(observer_->total_read_, data_one.size() + data_two.size());
+}
+
 }  // namespace chromeos