Change getDevices to use a DeviceCallback.

chrome/browser/chromeos/bluetooth/bluetooth_device.h

Index: chrome/browser/chromeos/bluetooth/bluetooth_device.h
diff --git a/chrome/browser/chromeos/bluetooth/bluetooth_device.h b/chrome/browser/chromeos/bluetooth/bluetooth_device.h
index 0064f48e11565148e3d5491f3308e11d00c1ceae..f3c62ddd0b40d2f6c5d3dc334b7b8911ed5d2e20 100644
--- a/chrome/browser/chromeos/bluetooth/bluetooth_device.h
+++ b/chrome/browser/chromeos/bluetooth/bluetooth_device.h
@@ -201,8 +201,8 @@ class BluetoothDevice : public BluetoothDeviceClient::Observer,
   typedef base::Callback<void(bool)> ProvidesServiceCallback;
 
   // Indicates whether this device provides the given service.
-  void ProvidesServiceWithName(const std::string& name,
-                               const ProvidesServiceCallback& callback);
+  virtual void ProvidesServiceWithName(const std::string& name,
+                                       const ProvidesServiceCallback& callback);
 
   // Indicates whether the device is currently pairing and expecting a
   // PIN Code to be returned.