Revert "Do not fall over when refreshing balance fails"

src/wallet/wallet2.cpp

@@ -309,8 +309,7 @@ void wallet2::refresh(size_t & blocks_fetched, bool& received_money)
       else
       {
         LOG_ERROR("pull_blocks failed, try_count=" << try_count);
-        //throw;
-        return;
+        throw;
       }
     }
   }