libbatteryservice: add interface to read individual battery properties

Change-Id: I089eb6348053a8a9c8bca59e57ed97b4af14825a
diff --git a/include/batteryservice/IBatteryPropertiesRegistrar.h b/include/batteryservice/IBatteryPropertiesRegistrar.h
index 8d28b1d..eca075d 100644
--- a/include/batteryservice/IBatteryPropertiesRegistrar.h
+++ b/include/batteryservice/IBatteryPropertiesRegistrar.h
@@ -26,6 +26,7 @@
 enum {
     REGISTER_LISTENER = IBinder::FIRST_CALL_TRANSACTION,
     UNREGISTER_LISTENER,
+    GET_PROPERTY,
 };
 
 class IBatteryPropertiesRegistrar : public IInterface {
@@ -34,6 +35,7 @@
 
     virtual void registerListener(const sp<IBatteryPropertiesListener>& listener) = 0;
     virtual void unregisterListener(const sp<IBatteryPropertiesListener>& listener) = 0;
+    virtual status_t getProperty(int id, struct BatteryProperty *val) = 0;
 };
 
 class BnBatteryPropertiesRegistrar : public BnInterface<IBatteryPropertiesRegistrar> {