Expose device RSSI and Tx power via the chrome.bluetooth API.

device/bluetooth/bluetooth_device_mac.h

Index: device/bluetooth/bluetooth_device_mac.h
diff --git a/device/bluetooth/bluetooth_device_mac.h b/device/bluetooth/bluetooth_device_mac.h
index ec87ff7ce29fb0e302896cae6999f87fd1aa8f28..1503f1dc12778fc11a76cd8e7f79c84f04a8b708 100644
--- a/device/bluetooth/bluetooth_device_mac.h
+++ b/device/bluetooth/bluetooth_device_mac.h
@@ -5,6 +5,8 @@
 #ifndef DEVICE_BLUETOOTH_BLUETOOTH_DEVICE_MAC_H_
 #define DEVICE_BLUETOOTH_BLUETOOTH_DEVICE_MAC_H_
 
+#import <IOBluetooth/IOBluetooth.h>
+
 #include <string>
 
 #include "base/basictypes.h"
@@ -32,6 +34,9 @@ class BluetoothDeviceMac : public BluetoothDevice {
   virtual uint16 GetVendorID() const OVERRIDE;
   virtual uint16 GetProductID() const OVERRIDE;
   virtual uint16 GetDeviceID() const OVERRIDE;
+  virtual int GetRSSI() const OVERRIDE;
+  virtual int GetCurrentHostTransmitPower() const OVERRIDE;
+  virtual int GetMaximumHostTransmitPower() const OVERRIDE;
   virtual bool IsPaired() const OVERRIDE;
   virtual bool IsConnected() const OVERRIDE;
   virtual bool IsConnectable() const OVERRIDE;
@@ -72,6 +77,11 @@ class BluetoothDeviceMac : public BluetoothDevice {
  private:
   friend class BluetoothAdapterMac;
 
+  // Implementation to read the host's transmit power level of type
+  // |power_level_type|.
+  int GetHostTransmitPower(
+      BluetoothHCITransmitPowerLevelType power_level_type) const;
+
   // List of observers interested in event notifications from us.
   ObserverList<Observer> observers_;