Migrate chrome.bluetooth API backend to use device::BluetoothDiscoverySession.

device/bluetooth/bluetooth_discovery_session.h

 // Copyright 2014 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 DEVICE_BLUETOOTH_BLUETOOTH_DISCOVERY_SESSION_H_
 #define DEVICE_BLUETOOTH_BLUETOOTH_DISCOVERY_SESSION_H_
 
 #include "base/callback.h"
 #include "base/memory/ref_counted.h"
 #include "base/memory/weak_ptr.h"
@@ skipping 40 matching lines @@
   // on error |error_callback| is called. After a successful invocation, the
   // adapter may or may not stop device discovery, depending on whether or not
   // other active discovery sessions are present. Users are highly encouraged
   // to call this method to end a discovery session, instead of relying on the
   // destructor, so that they can be notified of the result via the callback
   // arguments.
   virtual void Stop(const base::Closure& callback,
                     const ErrorCallback& error_callback);
 
  protected:
-  friend class BluetoothAdapter;
-  explicit BluetoothDiscoverySession(BluetoothAdapter* adapter);
+  BluetoothDiscoverySession();  // Called by mock.
 
  private:
+  friend class BluetoothAdapter;
+  explicit BluetoothDiscoverySession(scoped_refptr<BluetoothAdapter> adapter);
+
   // Internal callback invoked when a call to Stop has succeeded.
   void OnStop(const base::Closure& callback);
 
   // Marks this instance as inactive. Called by BluetoothAdapter to mark a
   // session as inactive in the case of an unexpected change to the adapter
   // discovery state.
   void MarkAsInactive();
 
   // Whether or not this instance represents an active discovery session.
   bool active_;
 
   // The adapter that created this instance.
   scoped_refptr<BluetoothAdapter> adapter_;
 
   // Note: This should remain the last member so it'll be destroyed and
   // invalidate its weak pointers before any other members are destroyed.
   base::WeakPtrFactory<BluetoothDiscoverySession> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(BluetoothDiscoverySession);
 };
 
 }  // namespace device
 
 #endif  // DEVICE_BLUETOOTH_BLUETOOTH_DISCOVERY_SESSION_H_