Implement BluetoothGattNotifySession::Stop on Android, 2nd attempt

device/bluetooth/bluetooth_remote_gatt_characteristic_unittest.cc

Index: device/bluetooth/bluetooth_remote_gatt_characteristic_unittest.cc
diff --git a/device/bluetooth/bluetooth_remote_gatt_characteristic_unittest.cc b/device/bluetooth/bluetooth_remote_gatt_characteristic_unittest.cc
index ec0310b5f65f3fb7fcb3b19e43c7419929d09ece..553618e3f3d1956a67c996c3434804101e8ea85e 100644
--- a/device/bluetooth/bluetooth_remote_gatt_characteristic_unittest.cc
+++ b/device/bluetooth/bluetooth_remote_gatt_characteristic_unittest.cc
@@ -1022,7 +1022,7 @@ TEST_F(BluetoothRemoteGattCharacteristicTest,
 #endif  // defined(OS_ANDROID)
 
 #if defined(OS_ANDROID) || defined(OS_MACOSX) || defined(OS_WIN)
-// Tests StartNotifySession success on a characteristic enabling Notify.
+// Tests StartNotifySession success on a characteristic that enabled Notify.
 TEST_F(BluetoothRemoteGattCharacteristicTest, StartNotifySession) {
   if (!PlatformSupportsLowEnergy()) {
     LOG(WARNING) << "Low Energy Bluetooth unavailable, skipping unit test.";
@@ -1035,7 +1035,7 @@ TEST_F(BluetoothRemoteGattCharacteristicTest, StartNotifySession) {
 #endif  // defined(OS_ANDROID) || defined(OS_MACOSX) || defined(OS_WIN)
 
 #if defined(OS_ANDROID) || defined(OS_MACOSX) || defined(OS_WIN)
-// Tests StartNotifySession success on a characteristic enabling Indicate.
+// Tests StartNotifySession success on a characteristic that enabled Indicate.
 TEST_F(BluetoothRemoteGattCharacteristicTest, StartNotifySession_OnIndicate) {
   if (!PlatformSupportsLowEnergy()) {
     LOG(WARNING) << "Low Energy Bluetooth unavailable, skipping unit test.";
@@ -1048,7 +1048,7 @@ TEST_F(BluetoothRemoteGattCharacteristicTest, StartNotifySession_OnIndicate) {
 #endif  // defined(OS_ANDROID) || defined(OS_MACOSX) || defined(OS_WIN)
 
 #if defined(OS_ANDROID) || defined(OS_MACOSX) || defined(OS_WIN)
-// Tests StartNotifySession success on a characteristic enabling Notify &
+// Tests StartNotifySession success on a characteristic that enabled Notify &
 // Indicate.
 TEST_F(BluetoothRemoteGattCharacteristicTest,
        StartNotifySession_OnNotifyAndIndicate) {
@@ -1088,6 +1088,7 @@ TEST_F(BluetoothRemoteGattCharacteristicTest, StartNotifySession_Multiple) {
       GetGattErrorCallback(Call::NOT_EXPECTED));
   EXPECT_EQ(0, callback_count_);
   SimulateGattNotifySessionStarted(characteristic1_);
+  base::RunLoop().RunUntilIdle();
   EXPECT_EQ(1, gatt_notify_characteristic_attempts_);
   EXPECT_EQ(2, callback_count_);
   EXPECT_EQ(0, error_callback_count_);
@@ -1130,6 +1131,7 @@ TEST_F(BluetoothRemoteGattCharacteristicTest,
   EXPECT_EQ(0, callback_count_);
   SimulateGattNotifySessionStartError(
       characteristic1_, BluetoothRemoteGattService::GATT_ERROR_FAILED);
+  base::RunLoop().RunUntilIdle();
   EXPECT_EQ(0, callback_count_);
   EXPECT_EQ(2, error_callback_count_);
   ASSERT_EQ(0u, notify_sessions_.size());
@@ -1169,6 +1171,45 @@ TEST_F(BluetoothRemoteGattCharacteristicTest, StartNotifySession_AfterDeleted) {
 }
 #endif  // defined(OS_ANDROID)
 
+#if defined(OS_ANDROID)
+// Tests StartNotifySession completing before chrome objects are deleted.
+TEST_F(BluetoothRemoteGattCharacteristicTest,
+       StartNotifySession_BeforeDeleted) {
+  ASSERT_NO_FATAL_FAILURE(
+      FakeCharacteristicBoilerplate(/* properties: NOTIFY */ 0x10));
+  SimulateGattDescriptor(
+      characteristic1_,
+      BluetoothRemoteGattDescriptor::ClientCharacteristicConfigurationUuid()
+          .canonical_value());
+  ASSERT_EQ(1u, characteristic1_->GetDescriptors().size());
+
+  characteristic1_->StartNotifySession(
+      GetNotifyCallback(Call::EXPECTED),
+      GetGattErrorCallback(Call::NOT_EXPECTED));
+  EXPECT_EQ(1, gatt_notify_characteristic_attempts_);
+  EXPECT_EQ(0, callback_count_);
+
+  SimulateGattNotifySessionStarted(characteristic1_);
+  ASSERT_EQ(1u, notify_sessions_.size());
+
+  std::string characteristic_identifier = characteristic1_->GetIdentifier();
+
+  EXPECT_EQ(characteristic_identifier,
+            notify_sessions_[0]->GetCharacteristicIdentifier());
+  EXPECT_EQ(characteristic1_, notify_sessions_[0]->GetCharacteristic());
+  EXPECT_TRUE(notify_sessions_[0]->IsActive());
+
+  DeleteDevice(device_);  // TODO(576906) delete only the characteristic.
+
+  base::RunLoop().RunUntilIdle();
+  EXPECT_TRUE("Did not crash!");
+  ASSERT_TRUE(notify_sessions_[0]);
+  EXPECT_EQ(characteristic_identifier,
+            notify_sessions_[0]->GetCharacteristicIdentifier());
+  EXPECT_FALSE(notify_sessions_[0]->IsActive());
+}
+#endif  // defined(OS_ANDROID)
+
 #if defined(OS_MACOSX) || defined(OS_WIN)
 // Tests StartNotifySession reentrant in start notify session success callback
 // and the reentrant start notify session success.
@@ -1287,6 +1328,604 @@ TEST_F(BluetoothRemoteGattCharacteristicTest,
 }
 #endif  // defined(OS_WIN)
 
+#if defined(OS_ANDROID)
+// Tests StopNotifySession success on a characteristic that enabled Notify.
+TEST_F(BluetoothRemoteGattCharacteristicTest, StopNotifySession) {
+  ASSERT_NO_FATAL_FAILURE(StartNotifyBoilerplate(
+      /* properties: NOTIFY */ 0x10,
+      /* expected_config_descriptor_value: NOTIFY */ 1));
+  EXPECT_EQ(1, gatt_write_descriptor_attempts_);
+
+  notify_sessions_[0]->Stop(GetStopNotifyCallback(Call::EXPECTED));
+  SimulateGattNotifySessionStopped(characteristic1_);
+  base::RunLoop().RunUntilIdle();
+
+  // Check that the right values were written to the descriptor.
+  EXPECT_EQ(2, gatt_write_descriptor_attempts_);
+  ASSERT_EQ(2u, last_write_value_.size());
+  EXPECT_EQ(0, last_write_value_[0]);
+  EXPECT_EQ(0, last_write_value_[1]);
+
+  // Check that the notify session is inactive.
+  EXPECT_FALSE(notify_sessions_[0]->IsActive());
+  EXPECT_FALSE(characteristic1_->IsNotifying());
+}
+#endif  // defined(OS_ANDROID)
+
+#if defined(OS_ANDROID)
+// Tests that deleted sessions are stopped.
+TEST_F(BluetoothRemoteGattCharacteristicTest,
+       StopNotifySession_SessionDeleted) {
+  ASSERT_NO_FATAL_FAILURE(StartNotifyBoilerplate(
+      /* properties: NOTIFY */ 0x10,
+      /* expected_config_descriptor_value: NOTIFY */ 1));
+  EXPECT_EQ(1, gatt_write_descriptor_attempts_);
+
+  notify_sessions_.clear();
+  SimulateGattNotifySessionStopped(characteristic1_);
+  base::RunLoop().RunUntilIdle();
+
+  // Check that the right values were written to the descriptor.
+  EXPECT_EQ(2, gatt_write_descriptor_attempts_);
+  ASSERT_EQ(2u, last_write_value_.size());
+  EXPECT_EQ(0, last_write_value_[0]);
+  EXPECT_EQ(0, last_write_value_[1]);
+
+  // Check that the notify session is inactive.
+  EXPECT_FALSE(characteristic1_->IsNotifying());
+}
+#endif  // defined(OS_ANDROID)
+
+#if defined(OS_ANDROID)
+// Tests that deleting the sessions before the stop callbacks have been
+// invoked does not cause problems.
+TEST_F(BluetoothRemoteGattCharacteristicTest,
+       StopNotifySession_SessionDeleted2) {
+  ASSERT_NO_FATAL_FAILURE(
+      FakeCharacteristicBoilerplate(/* properties: NOTIFY */ 0x10));
+
+#if !defined(OS_MACOSX)
+  // TODO(624017) enable for macosx
+  SimulateGattDescriptor(
+      characteristic1_,
+      BluetoothRemoteGattDescriptor::ClientCharacteristicConfigurationUuid()
+          .canonical_value());
+  ASSERT_EQ(1u, characteristic1_->GetDescriptors().size());
+#endif
+
+  // Start notify sessions.
+  characteristic1_->StartNotifySession(
+      GetNotifyCheckForPrecedingCalls(0),
+      GetGattErrorCallback(Call::NOT_EXPECTED));
+  characteristic1_->StartNotifySession(
+      GetNotifyCheckForPrecedingCalls(1),
+      GetGattErrorCallback(Call::NOT_EXPECTED));
+  EXPECT_EQ(0, callback_count_);
+  SimulateGattNotifySessionStarted(characteristic1_);
+  base::RunLoop().RunUntilIdle();
+  EXPECT_EQ(1, gatt_notify_characteristic_attempts_);
+  EXPECT_EQ(2, callback_count_);
+  EXPECT_EQ(0, error_callback_count_);
+  ASSERT_EQ(2u, notify_sessions_.size());
+  ASSERT_TRUE(notify_sessions_[0]);
+  ASSERT_TRUE(notify_sessions_[1]);
+  EXPECT_EQ(characteristic1_, notify_sessions_[0]->GetCharacteristic());
+  EXPECT_EQ(characteristic1_, notify_sessions_[1]->GetCharacteristic());
+  EXPECT_TRUE(notify_sessions_[0]->IsActive());
+  EXPECT_TRUE(notify_sessions_[1]->IsActive());
+  EXPECT_TRUE(characteristic1_->IsNotifying());
+
+  // Queue up stop events.
+  notify_sessions_[1]->Stop(GetStopNotifyCallback(Call::EXPECTED));
+  notify_sessions_[0]->Stop(GetStopNotifyCallback(Call::EXPECTED));
+
+  // Delete the notify sessions.
+  notify_sessions_.clear();
+
+  // Run the stop events.
+  base::RunLoop().RunUntilIdle();
+  SimulateGattNotifySessionStopped(characteristic1_);
+  base::RunLoop().RunUntilIdle();
+
+  // Check that the state is correct.
+  EXPECT_TRUE("Did not crash!");
+  EXPECT_FALSE(characteristic1_->IsNotifying());
+}
+#endif  // defined(OS_ANDROID)
+
+#if defined(OS_ANDROID)
+// Tests that deleted sessions are stopped.
+TEST_F(BluetoothRemoteGattCharacteristicTest, StopNotifySession_AfterDeleted) {
+  ASSERT_NO_FATAL_FAILURE(StartNotifyBoilerplate(
+      /* properties: NOTIFY */ 0x10,
+      /* expected_config_descriptor_value: NOTIFY */ 1));
+
+  // Check that the session is correctly setup
+  std::string characteristic_identifier = characteristic1_->GetIdentifier();
+  EXPECT_EQ(characteristic_identifier,
+            notify_sessions_[0]->GetCharacteristicIdentifier());
+  EXPECT_EQ(characteristic1_, notify_sessions_[0]->GetCharacteristic());
+  EXPECT_TRUE(notify_sessions_[0]->IsActive());
+
+  DeleteDevice(device_);  // TODO(576906) delete only the characteristic.
+
+  ResetEventCounts();
+  notify_sessions_[0]->Stop(GetStopNotifyCallback(Call::EXPECTED));
+
+  // Check that the callback does not arrive synchronously.
+  EXPECT_EQ(0, callback_count_);
+
+  // Trigger the stop callback
+  base::RunLoop().RunUntilIdle();
+  EXPECT_EQ(1, callback_count_);
+
+  EXPECT_TRUE("Did not crash!");
+  ASSERT_TRUE(notify_sessions_[0]);
+  EXPECT_EQ(characteristic_identifier,
+            notify_sessions_[0]->GetCharacteristicIdentifier());
+  EXPECT_FALSE(notify_sessions_[0]->IsActive());
+}
+#endif  // defined(OS_ANDROID)
+
+#if defined(OS_ANDROID)
+// Tests StopNotifySession success on a characteristic that enabled Indicate.
+TEST_F(BluetoothRemoteGattCharacteristicTest, StopNotifySession_OnIndicate) {
+  ASSERT_NO_FATAL_FAILURE(StartNotifyBoilerplate(
+      /* properties: INDICATE */ 0x20,
+      /* expected_config_descriptor_value: INDICATE */ 2));
+  EXPECT_EQ(1, gatt_write_descriptor_attempts_);
+
+  notify_sessions_[0]->Stop(GetStopNotifyCallback(Call::EXPECTED));
+  SimulateGattNotifySessionStopped(characteristic1_);
+  base::RunLoop().RunUntilIdle();
+
+  // Check that the right values were written to the descriptor.
+  EXPECT_EQ(2, gatt_write_descriptor_attempts_);
+  ASSERT_EQ(2u, last_write_value_.size());
+  EXPECT_EQ(0, last_write_value_[0]);
+  EXPECT_EQ(0, last_write_value_[1]);
+
+  // Check that the notify session is inactive.
+  EXPECT_FALSE(notify_sessions_[0]->IsActive());
+  EXPECT_FALSE(characteristic1_->IsNotifying());
+}
+#endif  // defined(OS_ANDROID)
+
+#if defined(OS_ANDROID)
+// Tests StopNotifySession success on a characteristic that enabled Notify &
+// Indicate.
+TEST_F(BluetoothRemoteGattCharacteristicTest,
+       StopNotifySession_OnNotifyAndIndicate) {
+  ASSERT_NO_FATAL_FAILURE(StartNotifyBoilerplate(
+      /* properties: NOTIFY and INDICATE bits set */ 0x30,
+      /* expected_config_descriptor_value: INDICATE */ 1));
+  EXPECT_EQ(1, gatt_write_descriptor_attempts_);
+
+  notify_sessions_[0]->Stop(GetStopNotifyCallback(Call::EXPECTED));
+  SimulateGattNotifySessionStopped(characteristic1_);
+  base::RunLoop().RunUntilIdle();
+
+  // Check that the right values were written to the descriptor.
+  EXPECT_EQ(2, gatt_write_descriptor_attempts_);
+  ASSERT_EQ(2u, last_write_value_.size());
+  EXPECT_EQ(0, last_write_value_[0]);
+  EXPECT_EQ(0, last_write_value_[1]);
+
+  // Check that the notify session is inactive.
+  EXPECT_FALSE(notify_sessions_[0]->IsActive());
+  EXPECT_FALSE(characteristic1_->IsNotifying());
+}
+#endif  // defined(OS_ANDROID)
+
+#if defined(OS_ANDROID)
+// Tests StopNotifySession error
+TEST_F(BluetoothRemoteGattCharacteristicTest, StopNotifySession_Error) {
+  ASSERT_NO_FATAL_FAILURE(StartNotifyBoilerplate(
+      /* properties: NOTIFY */ 0x10,
+      /* expected_config_descriptor_value: NOTIFY */ 1));
+
+  // Check that the notify session is active.
+  EXPECT_TRUE(notify_sessions_[0]->IsActive());
+  EXPECT_EQ(characteristic1_->GetIdentifier(),
+            notify_sessions_[0]->GetCharacteristicIdentifier());
+  EXPECT_EQ(characteristic1_, notify_sessions_[0]->GetCharacteristic());
+  EXPECT_TRUE(characteristic1_->IsNotifying());
+
+  notify_sessions_[0]->Stop(GetStopNotifyCallback(Call::EXPECTED));
+  SimulateGattNotifySessionStopError(
+      characteristic1_, BluetoothRemoteGattService::GATT_ERROR_UNKNOWN);
+  base::RunLoop().RunUntilIdle();
+
+  // Check that the notify session is inactive.
+  EXPECT_FALSE(notify_sessions_[0]->IsActive());
+  EXPECT_FALSE(characteristic1_->IsNotifying());
+}
+#endif  // defined(OS_ANDROID)
+
+#if defined(OS_ANDROID)
+// Tests multiple StopNotifySession calls for a single session.
+TEST_F(BluetoothRemoteGattCharacteristicTest, StopNotifySession_Multiple1) {
+  ASSERT_NO_FATAL_FAILURE(
+      FakeCharacteristicBoilerplate(/* properties: NOTIFY */ 0x10));
+
+#if !defined(OS_MACOSX)
+  // TODO(624017) enable for macosx
+  SimulateGattDescriptor(
+      characteristic1_,
+      BluetoothRemoteGattDescriptor::ClientCharacteristicConfigurationUuid()
+          .canonical_value());
+  ASSERT_EQ(1u, characteristic1_->GetDescriptors().size());
+#endif
+
+  // Start notify session
+  characteristic1_->StartNotifySession(
+      GetNotifyCallback(Call::EXPECTED),
+      GetGattErrorCallback(Call::NOT_EXPECTED));
+  EXPECT_EQ(0, callback_count_);
+  SimulateGattNotifySessionStarted(characteristic1_);
+  base::RunLoop().RunUntilIdle();
+  EXPECT_EQ(1, gatt_notify_characteristic_attempts_);
+  EXPECT_EQ(1, callback_count_);
+  EXPECT_EQ(0, error_callback_count_);
+  ASSERT_EQ(1u, notify_sessions_.size());
+  ASSERT_TRUE(notify_sessions_[0]);
+  EXPECT_EQ(characteristic1_, notify_sessions_[0]->GetCharacteristic());
+  EXPECT_TRUE(notify_sessions_[0]->IsActive());
+  EXPECT_TRUE(characteristic1_->IsNotifying());
+
+  // Stop the notify session twice
+  ResetEventCounts();
+  notify_sessions_[0]->Stop(GetStopNotifyCheckForPrecedingCalls(0));
+  notify_sessions_[0]->Stop(GetStopNotifyCheckForPrecedingCalls(1));
+  SimulateGattNotifySessionStopped(characteristic1_);
+  base::RunLoop().RunUntilIdle();
+
+  // Check that the notify session is inactive.
+  EXPECT_FALSE(notify_sessions_[0]->IsActive());
+  EXPECT_FALSE(characteristic1_->IsNotifying());
+}
+#endif  // defined(OS_ANDROID)
+
+#if defined(OS_ANDROID)
+// Tests multiple StartNotifySession calls and multiple StopNotifySession calls.
+TEST_F(BluetoothRemoteGattCharacteristicTest, StopNotifySession_Multiple2) {
+  ASSERT_NO_FATAL_FAILURE(
+      FakeCharacteristicBoilerplate(/* properties: NOTIFY */ 0x10));
+
+#if !defined(OS_MACOSX)
+  // TODO(624017) enable for macosx
+  SimulateGattDescriptor(
+      characteristic1_,
+      BluetoothRemoteGattDescriptor::ClientCharacteristicConfigurationUuid()
+          .canonical_value());
+  ASSERT_EQ(1u, characteristic1_->GetDescriptors().size());
+#endif
+
+  // Start notify sessions
+  characteristic1_->StartNotifySession(
+      GetNotifyCheckForPrecedingCalls(0),
+      GetGattErrorCallback(Call::NOT_EXPECTED));
+  characteristic1_->StartNotifySession(
+      GetNotifyCheckForPrecedingCalls(1),
+      GetGattErrorCallback(Call::NOT_EXPECTED));
+  EXPECT_EQ(0, callback_count_);
+  SimulateGattNotifySessionStarted(characteristic1_);
+  base::RunLoop().RunUntilIdle();
+  EXPECT_EQ(1, gatt_notify_characteristic_attempts_);
+  EXPECT_EQ(2, callback_count_);
+  EXPECT_EQ(0, error_callback_count_);
+  ASSERT_EQ(2u, notify_sessions_.size());
+  ASSERT_TRUE(notify_sessions_[0]);
+  ASSERT_TRUE(notify_sessions_[1]);
+  EXPECT_EQ(characteristic1_, notify_sessions_[0]->GetCharacteristic());
+  EXPECT_EQ(characteristic1_, notify_sessions_[1]->GetCharacteristic());
+  EXPECT_TRUE(notify_sessions_[0]->IsActive());
+  EXPECT_TRUE(notify_sessions_[1]->IsActive());
+  EXPECT_TRUE(characteristic1_->IsNotifying());
+
+  // Stop the notify sessions
+  notify_sessions_[1]->Stop(GetStopNotifyCheckForPrecedingCalls(2));
+  base::RunLoop().RunUntilIdle();
+  EXPECT_TRUE(notify_sessions_[0]->IsActive());
+  EXPECT_FALSE(notify_sessions_[1]->IsActive());
+  EXPECT_TRUE(characteristic1_->IsNotifying());
+
+  notify_sessions_[0]->Stop(GetStopNotifyCheckForPrecedingCalls(3));
+  SimulateGattNotifySessionStopped(characteristic1_);
+  base::RunLoop().RunUntilIdle();
+
+  // Check that the notify sessions is inactive.
+  EXPECT_FALSE(notify_sessions_[0]->IsActive());
+  EXPECT_FALSE(notify_sessions_[1]->IsActive());
+  EXPECT_FALSE(characteristic1_->IsNotifying());
+}
+#endif  // defined(OS_ANDROID)
+
+#if defined(OS_ANDROID)
+// Tests starting a new notify session before the previous stop request
+// resolves.
+TEST_F(BluetoothRemoteGattCharacteristicTest, StopNotifySession_StopStart) {
+  ASSERT_NO_FATAL_FAILURE(
+      FakeCharacteristicBoilerplate(/* properties: NOTIFY */ 0x10));
+  SimulateGattDescriptor(
+      characteristic1_,
+      BluetoothRemoteGattDescriptor::ClientCharacteristicConfigurationUuid()
+          .canonical_value());
+  ASSERT_EQ(1u, characteristic1_->GetDescriptors().size());
+
+  // Start notify session
+  ResetEventCounts();
+  characteristic1_->StartNotifySession(
+      GetNotifyCheckForPrecedingCalls(0),
+      GetGattErrorCallback(Call::NOT_EXPECTED));
+  SimulateGattNotifySessionStarted(characteristic1_);
+  base::RunLoop().RunUntilIdle();
+  ASSERT_EQ(1u, notify_sessions_.size());
+  ASSERT_TRUE(notify_sessions_[0]);
+  EXPECT_TRUE(notify_sessions_[0]->IsActive());
+
+  // Stop the notify session
+  notify_sessions_[0]->Stop(GetStopNotifyCheckForPrecedingCalls(1));
+
+  // Start another notify session
+  characteristic1_->StartNotifySession(
+      GetNotifyCheckForPrecedingCalls(2),
+      GetGattErrorCallback(Call::NOT_EXPECTED));
+
+  SimulateGattNotifySessionStopped(characteristic1_);
+  base::RunLoop().RunUntilIdle();
+  EXPECT_FALSE(notify_sessions_[0]->IsActive());
+
+  SimulateGattNotifySessionStarted(characteristic1_);
+  base::RunLoop().RunUntilIdle();
+  ASSERT_EQ(2u, notify_sessions_.size());
+  ASSERT_TRUE(notify_sessions_[0]);
+  EXPECT_FALSE(notify_sessions_[0]->IsActive());
+  ASSERT_TRUE(notify_sessions_[1]);
+  EXPECT_TRUE(notify_sessions_[1]->IsActive());
+  EXPECT_TRUE(characteristic1_->IsNotifying());
+}
+#endif  // defined(OS_ANDROID)
+
+#if defined(OS_ANDROID)
+TEST_F(BluetoothRemoteGattCharacteristicTest,
+       StopNotifySession_StartStopStart) {
+  ASSERT_NO_FATAL_FAILURE(StartNotifyBoilerplate(
+      /* properties: NOTIFY */ 0x10,
+      /* expected_config_descriptor_value: NOTIFY */ 1));
+
+  // Check that the initial notify session is active.
+  EXPECT_TRUE(notify_sessions_[0]->IsActive());
+  EXPECT_EQ(characteristic1_->GetIdentifier(),
+            notify_sessions_[0]->GetCharacteristicIdentifier());
+  EXPECT_EQ(characteristic1_, notify_sessions_[0]->GetCharacteristic());
+  EXPECT_TRUE(characteristic1_->IsNotifying());
+
+  // Queue up the first event.
+  ResetEventCounts();
+  characteristic1_->StartNotifySession(
+      GetNotifyCheckForPrecedingCalls(0),
+      GetGattErrorCallback(Call::NOT_EXPECTED));
+
+  // Queue up the second event.
+  notify_sessions_[0]->Stop(GetStopNotifyCheckForPrecedingCalls(1));
+
+  // Queue up the third event.
+  characteristic1_->StartNotifySession(
+      GetNotifyCheckForPrecedingCalls(2),
+      GetGattErrorCallback(Call::NOT_EXPECTED));
+
+  // Run the event loop to resolve all three events.
+  base::RunLoop().RunUntilIdle();
+
+  // Check the state of all the sessions.
+  ASSERT_EQ(3u, notify_sessions_.size());
+  EXPECT_EQ(characteristic1_->GetIdentifier(),
+            notify_sessions_[0]->GetCharacteristicIdentifier());
+  EXPECT_EQ(characteristic1_, notify_sessions_[0]->GetCharacteristic());
+  EXPECT_FALSE(notify_sessions_[0]->IsActive());
+
+  EXPECT_EQ(characteristic1_->GetIdentifier(),
+            notify_sessions_[1]->GetCharacteristicIdentifier());
+  EXPECT_EQ(characteristic1_, notify_sessions_[1]->GetCharacteristic());
+  EXPECT_TRUE(notify_sessions_[1]->IsActive());
+
+  EXPECT_EQ(characteristic1_->GetIdentifier(),
+            notify_sessions_[2]->GetCharacteristicIdentifier());
+  EXPECT_EQ(characteristic1_, notify_sessions_[2]->GetCharacteristic());
+  EXPECT_TRUE(notify_sessions_[2]->IsActive());
+
+  EXPECT_TRUE(characteristic1_->IsNotifying());
+}
+#endif
+
+#if defined(OS_ANDROID)
+// Tests starting a new notify session before the previous stop requests
+// resolve.
+TEST_F(BluetoothRemoteGattCharacteristicTest, StopNotifySession_StopStopStart) {
+  ASSERT_NO_FATAL_FAILURE(
+      FakeCharacteristicBoilerplate(/* properties: NOTIFY */ 0x10));
+  SimulateGattDescriptor(
+      characteristic1_,
+      BluetoothRemoteGattDescriptor::ClientCharacteristicConfigurationUuid()
+          .canonical_value());
+  ASSERT_EQ(1u, characteristic1_->GetDescriptors().size());
+
+  // Start notify session
+  ResetEventCounts();
+  characteristic1_->StartNotifySession(
+      GetNotifyCheckForPrecedingCalls(0),
+      GetGattErrorCallback(Call::NOT_EXPECTED));
+  SimulateGattNotifySessionStarted(characteristic1_);
+  base::RunLoop().RunUntilIdle();
+  ASSERT_EQ(1u, notify_sessions_.size());
+  ASSERT_TRUE(notify_sessions_[0]);
+  EXPECT_TRUE(notify_sessions_[0]->IsActive());
+  EXPECT_EQ(1, gatt_write_descriptor_attempts_);
+
+  // Stop the notify session twice
+  notify_sessions_[0]->Stop(GetStopNotifyCheckForPrecedingCalls(1));
+  notify_sessions_[0]->Stop(GetStopNotifyCheckForPrecedingCalls(2));
+
+  // Check that the right values were written to the descriptor.
+  EXPECT_EQ(2, gatt_write_descriptor_attempts_);
+  ASSERT_EQ(2u, last_write_value_.size());
+  EXPECT_EQ(0, last_write_value_[0]);
+  EXPECT_EQ(0, last_write_value_[1]);
+
+  // Start another notify session
+  characteristic1_->StartNotifySession(
+      GetNotifyCheckForPrecedingCalls(3),
+      GetGattErrorCallback(Call::NOT_EXPECTED));
+
+  // Check that nothing was written by the StartNotifySession call above
+  EXPECT_EQ(2, gatt_write_descriptor_attempts_);
+
+  SimulateGattNotifySessionStopped(characteristic1_);
+  base::RunLoop().RunUntilIdle();
+  EXPECT_FALSE(notify_sessions_[0]->IsActive());
+
+  SimulateGattNotifySessionStarted(characteristic1_);
+  base::RunLoop().RunUntilIdle();
+
+  // Check that the right values were written to the descriptor.
+  EXPECT_EQ(3, gatt_write_descriptor_attempts_);
+  ASSERT_EQ(2u, last_write_value_.size());
+  EXPECT_EQ(1, last_write_value_[0]);
+  EXPECT_EQ(0, last_write_value_[1]);
+
+  // Check the notify state
+  ASSERT_EQ(2u, notify_sessions_.size());
+  ASSERT_TRUE(notify_sessions_[0]);
+  EXPECT_FALSE(notify_sessions_[0]->IsActive());
+  ASSERT_TRUE(notify_sessions_[1]);
+  EXPECT_TRUE(notify_sessions_[1]->IsActive());
+  EXPECT_TRUE(characteristic1_->IsNotifying());
+}
+#endif  // defined(OS_ANDROID)
+
+#if defined(OS_ANDROID)
+TEST_F(BluetoothRemoteGattCharacteristicTest,
+       StopNotifySession_Reentrant_Success_Stop) {
+  ASSERT_NO_FATAL_FAILURE(
+      FakeCharacteristicBoilerplate(/* properties: NOTIFY */ 0x10));
+  SimulateGattDescriptor(
+      characteristic1_,
+      BluetoothRemoteGattDescriptor::ClientCharacteristicConfigurationUuid()
+          .canonical_value());
+  ASSERT_EQ(1u, characteristic1_->GetDescriptors().size());
+
+  // Start notify session
+  characteristic1_->StartNotifySession(
+      base::Bind(
+          [](BluetoothRemoteGattCharacteristic::NotifySessionCallback
+                 notifyCallback,
+             base::Closure stopNotifyCallback,
+             std::unique_ptr<BluetoothGattNotifySession> session) {
+            BluetoothGattNotifySession* s = session.get();
+            notifyCallback.Run(std::move(session));
+            s->Stop(stopNotifyCallback);
+          },
+          GetNotifyCallback(Call::EXPECTED),
+          GetStopNotifyCallback(Call::EXPECTED)),
+      GetGattErrorCallback(Call::NOT_EXPECTED));
+
+  SimulateGattNotifySessionStarted(characteristic1_);
+  base::RunLoop().RunUntilIdle();
+  ASSERT_EQ(1u, notify_sessions_.size());
+  ASSERT_TRUE(notify_sessions_[0]);
+  EXPECT_FALSE(notify_sessions_[0]->IsActive());
+  EXPECT_TRUE(characteristic1_->IsNotifying());
+
+  SimulateGattNotifySessionStopped(characteristic1_);
+  base::RunLoop().RunUntilIdle();
+  EXPECT_FALSE(notify_sessions_[0]->IsActive());
+  EXPECT_FALSE(characteristic1_->IsNotifying());
+}
+#endif
+
+#if defined(OS_ANDROID)
+TEST_F(BluetoothRemoteGattCharacteristicTest,
+       StopNotifySession_Reentrant_Stop_StartSuccess) {
+  ASSERT_NO_FATAL_FAILURE(StartNotifyBoilerplate(
+      /* properties: NOTIFY */ 0x10,
+      /* expected_config_descriptor_value: NOTIFY */ 1));
+
+  // Check that the notify session is active.
+  EXPECT_TRUE(notify_sessions_[0]->IsActive());
+  EXPECT_EQ(characteristic1_->GetIdentifier(),
+            notify_sessions_[0]->GetCharacteristicIdentifier());
+  EXPECT_EQ(characteristic1_, notify_sessions_[0]->GetCharacteristic());
+  EXPECT_TRUE(characteristic1_->IsNotifying());
+
+  notify_sessions_[0]->Stop(base::Bind(
+      [](BluetoothRemoteGattCharacteristic* characteristic,
+         BluetoothRemoteGattCharacteristic::NotifySessionCallback
+             notifyCallback,
+         BluetoothRemoteGattCharacteristic::ErrorCallback errorCallback) {
+        characteristic->StartNotifySession(notifyCallback, errorCallback);
+      },
+      characteristic1_, GetNotifyCallback(Call::EXPECTED),
+      GetGattErrorCallback(Call::NOT_EXPECTED)));
+
+  SimulateGattNotifySessionStopped(characteristic1_);
+  base::RunLoop().RunUntilIdle();
+  EXPECT_FALSE(notify_sessions_[0]->IsActive());
+  EXPECT_FALSE(characteristic1_->IsNotifying());
+
+  SimulateGattNotifySessionStarted(characteristic1_);
+  base::RunLoop().RunUntilIdle();
+  ASSERT_EQ(2u, notify_sessions_.size());
+  ASSERT_TRUE(notify_sessions_[0]);
+  ASSERT_TRUE(notify_sessions_[1]);
+  EXPECT_EQ(characteristic1_, notify_sessions_[0]->GetCharacteristic());
+  EXPECT_EQ(characteristic1_, notify_sessions_[1]->GetCharacteristic());
+  EXPECT_FALSE(notify_sessions_[0]->IsActive());
+  EXPECT_TRUE(notify_sessions_[1]->IsActive());
+  EXPECT_TRUE(characteristic1_->IsNotifying());
+}
+#endif
+
+#if defined(OS_ANDROID)
+TEST_F(BluetoothRemoteGattCharacteristicTest,
+       StopNotifySession_Reentrant_Stop_StartError) {
+  ASSERT_NO_FATAL_FAILURE(StartNotifyBoilerplate(
+      /* properties: NOTIFY */ 0x10,
+      /* expected_config_descriptor_value: NOTIFY */ 1));
+
+  // Check that the notify session is active.
+  EXPECT_TRUE(notify_sessions_[0]->IsActive());
+  EXPECT_EQ(characteristic1_->GetIdentifier(),
+            notify_sessions_[0]->GetCharacteristicIdentifier());
+  EXPECT_EQ(characteristic1_, notify_sessions_[0]->GetCharacteristic());
+  EXPECT_TRUE(characteristic1_->IsNotifying());
+
+  notify_sessions_[0]->Stop(base::Bind(
+      [](BluetoothRemoteGattCharacteristic* characteristic,
+         BluetoothRemoteGattCharacteristic::NotifySessionCallback
+             notifyCallback,
+         BluetoothRemoteGattCharacteristic::ErrorCallback errorCallback) {
+        characteristic->StartNotifySession(notifyCallback, errorCallback);
+      },
+      characteristic1_, GetNotifyCallback(Call::NOT_EXPECTED),
+      GetGattErrorCallback(Call::EXPECTED)));
+
+  SimulateGattNotifySessionStopped(characteristic1_);
+  base::RunLoop().RunUntilIdle();
+  EXPECT_FALSE(notify_sessions_[0]->IsActive());
+  EXPECT_FALSE(characteristic1_->IsNotifying());
+
+  SimulateGattNotifySessionStartError(
+      characteristic1_, BluetoothRemoteGattService::GATT_ERROR_FAILED);
+  base::RunLoop().RunUntilIdle();
+  ASSERT_EQ(1u, notify_sessions_.size());
+  ASSERT_TRUE(notify_sessions_[0]);
+  EXPECT_EQ(characteristic1_, notify_sessions_[0]->GetCharacteristic());
+  EXPECT_FALSE(notify_sessions_[0]->IsActive());
+  EXPECT_FALSE(characteristic1_->IsNotifying());
+}
+#endif
+
 #if defined(OS_ANDROID) || defined(OS_MACOSX) || defined(OS_WIN)
 // Tests Characteristic Value changes during a Notify Session.
 TEST_F(BluetoothRemoteGattCharacteristicTest, GattCharacteristicValueChanged) {