Remove notices on mysql query failures

Zend only has this sort of behavior when mysql.trace_mode is
enabled, but it's off by default. Since the mysql library is deprecated
and people should be using mysqli, it makes sense to emulate mysqli's
behavior here and not warn at all rather than trying to implement
mysql.trace_mode.

Closes #1140

Reviewed By: @markw65

Differential Revision: D1000998

Pulled By: @scannell

hphp/runtime/ext/ext_mysql.cpp

@@ -1021,8 +1021,10 @@ static Variant php_mysql_do_query_general(const String& query, CVarRef link_id,
   }
 
   if (mysql_real_query(conn, query.data(), query.size())) {
+#ifdef HHVM_MYSQL_TRACE_MODE
     raise_notice("runtime/ext_mysql: failed executing [%s] [%s]", query.data(),
                  mysql_error(conn));
+#endif
 
     // When we are timed out, and we're SELECT-ing, we're potentially
     // running a long query on the server without waiting for any results
@@ -1109,8 +1111,10 @@ Variant f_mysql_multi_query(const String& query, CVarRef link_identifier /* = nu
   }
 
   if (mysql_real_query(conn, query.data(), query.size())) {
+#ifdef HHVM_MYSQL_TRACE_MODE
     raise_notice("runtime/ext_mysql: failed executing [%s] [%s]", query.data(),
                   mysql_error(conn));
+#endif
       // turning this off clears the errors
       if (!mysql_set_server_option(conn, MYSQL_OPTION_MULTI_STATEMENTS_OFF)) {
         mySQL->m_multi_query = false;