Bug#23240 --init_file statements with NOW() reports '1970-01-01 11:00:00'as the date time

- Starting time of a query sent by bootstrapping wasn't initialized
  and starting time defaulted to 0. This later used value by NOW-
  item and was translated to 1970-01-01 11:00:00.
- Marketing the time with thd->set_time() before the call to
  mysql_parse resolves this issue.
- set_time was refactored to be part of the thd->init_for_queries-
  process.

sql/sql_class.cc

@@ -317,6 +317,7 @@ void THD::init(void)
 
 void THD::init_for_queries()
 {
+  set_time(); 
   ha_enable_transaction(this,TRUE);
 
   reset_root_defaults(mem_root, variables.query_alloc_block_size,