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

content/common/bluetooth/bluetooth_device.cc

Index: content/common/bluetooth/bluetooth_device.cc
diff --git a/content/common/bluetooth/bluetooth_device.cc b/content/common/bluetooth/bluetooth_device.cc
index c2b3bcbf355dd36684e586926d3708890c2ba5c2..6e9658042c2a11fb6d9718c83bcf433974e83415 100644
--- a/content/common/bluetooth/bluetooth_device.cc
+++ b/content/common/bluetooth/bluetooth_device.cc
@@ -11,8 +11,8 @@ namespace content {
 BluetoothDevice::BluetoothDevice()
     : id(""),
       name(base::string16()),
-      tx_power(device::BluetoothDevice::kUnknownPower),
-      rssi(device::BluetoothDevice::kUnknownPower),
+      tx_power(device::BluetoothDevice::kUnknownTxPower),
+      rssi(device::BluetoothDevice::kUnknownRSSI),
       uuids() {}
 
 BluetoothDevice::BluetoothDevice(
@@ -40,10 +40,4 @@ std::vector<std::string> BluetoothDevice::UUIDsFromBluetoothUUIDs(
   return uuids;
 }
 
-// static
-int8_t BluetoothDevice::ValidatePower(int16_t power) {
-  return ((power < -127) || (power > 127)) ? BluetoothDevice::kUnknownPower
-                                           : power;
-}
-
 }  // namespace content