Implement finding BLE connections in chrome://proximity-auth.

components/proximity_auth/ble/bluetooth_low_energy_connection_finder.h

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef COMPONENTS_PROXIMITY_AUTH_BLE_BLUETOOTH_LOW_ENERGY_CONNECTION_FINDER_H
 #define COMPONENTS_PROXIMITY_AUTH_BLE_BLUETOOTH_LOW_ENERGY_CONNECTION_FINDER_H
 
 #include <set>
 #include <string>
 
@@ skipping 80 matching lines @@
 
   // Stops the discovery session given by |discovery_session_|.
   void StopDiscoverySession();
 
   // Checks if a service with |service_uuid| is offered by |remote_device|.
   bool HasService(device::BluetoothDevice* remote_device);
 
   // Restarts the discovery session after creating |connection_| fails.
   void RestartDiscoverySessionWhenReady();
 
+  // Used to invokes |connection_callback_| asynchronously, decoupling the

[sacomoto, 2015/08/10 19:40:28]

nit: s/invokes/invoke/

[Tim Song, 2015/08/10 22:17:55]

Done.

+  // callback invocation from the ConnectionObserver callstack.
+  void InvokeCallbackAsync();
+
   // Returns the device with |device_address|.
   device::BluetoothDevice* GetDevice(std::string device_address);
 
   // The uuid of the service it looks for to establish a GattConnection.
   device::BluetoothUUID remote_service_uuid_;
 
   // Characteristic used to send data to the remote device.
   device::BluetoothUUID to_peripheral_char_uuid_;
 
   // Characteristic used to receive data from the remote device.
@@ skipping 24 matching lines @@
   int max_number_of_tries_;
 
   base::WeakPtrFactory<BluetoothLowEnergyConnectionFinder> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(BluetoothLowEnergyConnectionFinder);
 };
 
 }  // namespace proximity_auth
 
 #endif  // COMPONENTS_PROXIMITY_AUTH_BLE_BLUETOOTH_CONNECTION_FINDER_H