return value fix

Change-Id: Id23dc2cf7f25efbf778a853403e43dd1176d5e33

src/core/tracker.h

@@ -195,7 +195,7 @@ class Tracker {
       util::HsaRsrcFactory::Instance().HsaApi()->hsa_signal_store_screlease(orig_signal, signal_value);
     }
 
-    Context::Handler(signal_value, arg);
+    return Context::Handler(signal_value, arg);
   }
 
   private: