WL#1034 update

fix bug with DROP EVENT non_existant; giving back OK + warning


sql/share/errmsg.txt:
  fix error message
sql/sql_parse.cc:
  check the result from the function so in case of non-existing
  event don't return OK which will make the error already thrown
  an warning

sql/share/errmsg.txt

@@ -5726,7 +5726,7 @@ ER_EVENT_ALREADY_EXISTS
 ER_EVENT_STORE_FAILED
         eng "Failed to store event %s. Error code %d from storage engine."
 ER_EVENT_DOES_NOT_EXIST
-        eng "Event %s does not exist"
+        eng "Unknown event '%s'"
 ER_EVENT_CANT_ALTER
         eng "Failed to alter event %s"
 ER_EVENT_DROP_FAILED

sql/sql_parse.cc

@@ -3696,7 +3696,7 @@ mysql_execute_command(THD *thd)
         res= evex_update_event(thd, lex->et, lex->spname);
         break;
       case SQLCOM_DROP_EVENT:
-        evex_drop_event(thd, lex->et, lex->drop_if_exists);
+        res= evex_drop_event(thd, lex->et, lex->drop_if_exists);
       default:;
       }
       if (!res)