bluetooth: Return int8_t and use -128 for unknown tx power.

device/bluetooth/bluetooth_device_android.cc

 // 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.
 
 #include "device/bluetooth/bluetooth_device_android.h"
 
 #include "base/android/context_utils.h"
 #include "base/android/jni_android.h"
 #include "base/android/jni_array.h"
 #include "base/android/jni_string.h"
@@ skipping 122 matching lines @@
       env, Java_ChromeBluetoothDevice_getUuids(env, j_device_.obj()).obj(),
       &uuid_strings);
   BluetoothDevice::UUIDList uuids;
   uuids.reserve(uuid_strings.size());
   for (auto uuid_string : uuid_strings) {
     uuids.push_back(BluetoothUUID(uuid_string));
   }
   return uuids;
 }
 
-int16_t BluetoothDeviceAndroid::GetInquiryRSSI() const {
+base::Optional<int8_t> BluetoothDeviceAndroid::GetInquiryRSSI() const {
   NOTIMPLEMENTED();
-  return kUnknownPower;
+  return base::Optional<int8_t>();
 }
 
-int16_t BluetoothDeviceAndroid::GetInquiryTxPower() const {
+base::Optional<int8_t> BluetoothDeviceAndroid::GetInquiryTxPower() const {
   NOTIMPLEMENTED();
-  return kUnknownPower;
+  return base::Optional<int8_t>();
 }
 
 bool BluetoothDeviceAndroid::ExpectingPinCode() const {
   NOTIMPLEMENTED();
   return false;
 }
 
 bool BluetoothDeviceAndroid::ExpectingPasskey() const {
   NOTIMPLEMENTED();
   return false;
@@ skipping 134 matching lines @@
       AttachCurrentThread(), j_device_.obj(),
       base::android::GetApplicationContext());
 }
 
 void BluetoothDeviceAndroid::DisconnectGatt() {
   Java_ChromeBluetoothDevice_disconnectGatt(AttachCurrentThread(),
                                             j_device_.obj());
 }
 
 }  // namespace device