Adding BluetoothTestBase::CheckNotifySessionValue() method

device/bluetooth/test/bluetooth_test_mac.mm

Index: device/bluetooth/test/bluetooth_test_mac.mm
diff --git a/device/bluetooth/test/bluetooth_test_mac.mm b/device/bluetooth/test/bluetooth_test_mac.mm
index eb4bf905e330bb81166f50a4af60aa57b42aeeff..a468c7eb536115efc484a01e7bc417c3e5fc67e9 100644
--- a/device/bluetooth/test/bluetooth_test_mac.mm
+++ b/device/bluetooth/test/bluetooth_test_mac.mm
@@ -133,6 +133,12 @@ void BluetoothTestMac::InitWithFakeAdapter() {
   }
 }
 
+void BluetoothTestMac::ResetEventCounts() {
+  BluetoothTestBase::ResetEventCounts();
+  last_notify_value = false;
+  gatt_notify_characteristic_attempts_ = 0;
+}
+
 BluetoothDevice* BluetoothTestMac::SimulateLowEnergyDevice(int device_ordinal) {
   TestBluetoothAdapterObserver observer(adapter_);
   CBCentralManager* central_manager = adapter_mac_->low_energy_central_manager_;
@@ -465,6 +471,23 @@ void BluetoothTestMac::SimulateGattCharacteristicRemoved(
   [peripheral_mock mockDidDiscoverEvents];
 }
 
+void BluetoothTestMac::ExpectedChangeNotifyValueAttempts(int attempts) {
+  EXPECT_EQ(attempts, gatt_notify_characteristic_attempts_);
+}
+
+void BluetoothTestMac::ExpectedNotifyValue(
+    NotifyValueState expected_value_state) {
+  switch (expected_value_state) {
+    case NotifyValueState::NONE:
+      EXPECT_FALSE(last_notify_value);
+      break;
+    case NotifyValueState::NOTIFY:
+    case NotifyValueState::INDICATE:
+      EXPECT_TRUE(last_notify_value);
+      break;
+  }
+}
+
 void BluetoothTestMac::OnFakeBluetoothDeviceConnectGattCalled() {
   gatt_connection_attempts_++;
 }