Add support for local services/characteristics/descriptors.

device/bluetooth/bluetooth_gatt_service.h

Index: device/bluetooth/bluetooth_gatt_service.h
diff --git a/device/bluetooth/bluetooth_gatt_service.h b/device/bluetooth/bluetooth_gatt_service.h
index fe4bf1c5dd0fdc30fa49c3f04fd64bfc862cb48d..3f558d0a97509d31854b0026b3370d81766116b9 100644
--- a/device/bluetooth/bluetooth_gatt_service.h
+++ b/device/bluetooth/bluetooth_gatt_service.h
@@ -7,6 +7,7 @@
 
 #include <stdint.h>
 
+#include <string>
 #include <vector>
 
 #include "base/callback.h"
@@ -142,7 +143,8 @@ class DEVICE_BLUETOOTH_EXPORT BluetoothGattService {
   };
 
   // The ErrorCallback is used by methods to asynchronously report errors.
-  typedef base::Closure ErrorCallback;
+  using ErrorCallback = base::Callback<void(const std::string& error_name,

[scheib, 2016/04/12 18:05:46]

error_name should not be a string. We should not be exposing DBUS details in the
cross platform interface. This interface should explicitly document what may be
returned. A descriptive string for logging/output to console is fine, but any
code that program logic may depend on should be an enumeration (or nothing -
just the implicit error of the error callback).

[rkc, 2016/04/13 22:47:25]

Done.

+                                            const std::string& error_message)>;
 
   virtual ~BluetoothGattService();