Add Gtest to test watchdog

Change-Id: Ia0268b6b18999b6dd6cfd26bcadcff25734306f0
Signed-off-by: Vishwanatha Subbanna <vishwa@linux.vnet.ibm.com>
diff --git a/watchdog.hpp b/watchdog.hpp
index 79df438..cb26b7e 100644
--- a/watchdog.hpp
+++ b/watchdog.hpp
@@ -9,8 +9,8 @@
 {
 namespace watchdog
 {
-using WatchdogInherits = sdbusplus::server::object::object<
-        sdbusplus::xyz::openbmc_project::State::server::Watchdog>;
+namespace Base = sdbusplus::xyz::openbmc_project::State::server;
+using WatchdogInherits = sdbusplus::server::object::object<Base::Watchdog>;
 
 /** @class Watchdog
  *  @brief OpenBMC watchdog implementation.
@@ -46,6 +46,12 @@
             // Nothing
         }
 
+        /** @brief Since we are overriding the setter-enabled but not the
+         *         getter-enabled, we need to have this using in order to
+         *         allow passthrough usage of the getter-enabled.
+         */
+        using Base::Watchdog::enabled;
+
         /** @brief Enable or disable watchdog
          *         If a watchdog state is changed from disable to enable,
          *         the watchdog timer is set with the default expiration