Hook up RSSI and host transmit power Bluetooth device properties for ChromeOS.

device/bluetooth/bluetooth_device.h

Index: device/bluetooth/bluetooth_device.h
diff --git a/device/bluetooth/bluetooth_device.h b/device/bluetooth/bluetooth_device.h
index 7dce44f5bcdda1736bfd43db92ed24a209f3f956..a1825948b3c8b2354b23b9a2d2f4124987cbb355 100644
--- a/device/bluetooth/bluetooth_device.h
+++ b/device/bluetooth/bluetooth_device.h
@@ -404,6 +404,12 @@ class BluetoothDevice {
       const base::Closure& callback,
       const ErrorCallback& error_callback) = 0;
 
+  // Starts monitoring the connection properties, RSSI and TX power. These
+  // properties will be tracked, and updated when their values change. Exactly
+  // one of |callback| or |error_callback| will be run.
+  virtual void StartConnectionMonitor(const base::Closure& callback,
+                                      const ErrorCallback& error_callback) = 0;
+
   // Returns the list of discovered GATT services.
   virtual std::vector<BluetoothGattService*> GetGattServices() const;