Implement BluetoothRemoteGattCharacteristicWin::StartNotifySession and related unit tests

device/bluetooth/bluetooth_low_energy_win.h

Index: device/bluetooth/bluetooth_low_energy_win.h
diff --git a/device/bluetooth/bluetooth_low_energy_win.h b/device/bluetooth/bluetooth_low_energy_win.h
index cd7150d18418ec73e53fd89f17cc346eb4ba7028..6fb330a88c4e960b916e6b3eab522cee1660b933 100644
--- a/device/bluetooth/bluetooth_low_energy_win.h
+++ b/device/bluetooth/bluetooth_low_energy_win.h
@@ -176,6 +176,25 @@ class DEVICE_BLUETOOTH_EXPORT BluetoothLowEnergyWrapper {
       const PBTH_LE_GATT_CHARACTERISTIC characteristic,
       PBTH_LE_GATT_CHARACTERISTIC_VALUE new_value);
 
+  // Register GATT events of |event_type| in the service with service device
+  // path |service_path|. |event_parameter| is the event's parameter. |callback|
+  // is the function to be invoked if the event happened. |context| is the input
+  // parameter to be given back through |callback|. |*out_handle| stores the
+  // unique handle in OS for this registration.
+  virtual HRESULT RegisterGattEvents(base::FilePath& service_path,
+                                     BTH_LE_GATT_EVENT_TYPE event_type,
+                                     PVOID event_parameter,
+                                     PFNBLUETOOTH_GATT_EVENT_CALLBACK callback,
+                                     PVOID context,
+                                     BLUETOOTH_GATT_EVENT_HANDLE* out_handle);
+  virtual HRESULT UnregisterGattEvent(BLUETOOTH_GATT_EVENT_HANDLE event_handle);
+
+  // Writes |descriptor| value in service with service device path
+  // |service_path| to |*new_value|.
+  virtual HRESULT WriteDescriptorValue(base::FilePath& service_path,
+                                       const PBTH_LE_GATT_DESCRIPTOR descriptor,
+                                       PBTH_LE_GATT_DESCRIPTOR_VALUE new_value);
+
  protected:
   BluetoothLowEnergyWrapper();
   virtual ~BluetoothLowEnergyWrapper();