device/bluetooth: Move GATT observer methods to BluetoothAdapter::Observer.

device/bluetooth/bluetooth_device_win.h

Index: device/bluetooth/bluetooth_device_win.h
diff --git a/device/bluetooth/bluetooth_device_win.h b/device/bluetooth/bluetooth_device_win.h
index b403cf6dff4231052fb451621fdcd0c57bab5ebc..aa262bd48d445cf434855092c202a92c11b8b08d 100644
--- a/device/bluetooth/bluetooth_device_win.h
+++ b/device/bluetooth/bluetooth_device_win.h
@@ -30,10 +30,6 @@ class BluetoothDeviceWin : public BluetoothDevice {
   virtual ~BluetoothDeviceWin();
 
   // BluetoothDevice override
-  virtual void AddObserver(
-      device::BluetoothDevice::Observer* observer) OVERRIDE;
-  virtual void RemoveObserver(
-      device::BluetoothDevice::Observer* observer) OVERRIDE;
   virtual uint32 GetBluetoothClass() const OVERRIDE;
   virtual std::string GetAddress() const OVERRIDE;
   virtual VendorIDSource GetVendorIDSource() const OVERRIDE;
@@ -96,9 +92,6 @@ class BluetoothDeviceWin : public BluetoothDevice {
   net::NetLog* net_log_;
   net::NetLog::Source net_log_source_;
 
-  // List of observers interested in event notifications from us.
-  ObserverList<Observer> observers_;
-
   // The Bluetooth class of the device, a bitmask that may be decoded using
   // https://www.bluetooth.org/Technical/AssignedNumbers/baseband.htm
   uint32 bluetooth_class_;