[sql] Import reference version of SQLite 3.8.7.4.

third_party/sqlite/sqlite-src-3080704/test/threadtest2.c

 /*
 ** 2004 January 13
 **
 ** The author disclaims copyright to this source code.  In place of
 ** a legal notice, here is a blessing:
 **
 **    May you do good and not evil.
 **    May you find forgiveness for yourself and forgive others.
 **    May you share freely, never taking more than you give.
 **
@@ skipping 113 matching lines @@
     pthread_join(aThread[i], 0);
   }
   if( !all_stop ){
     printf("Everything seems ok.\n");
     return 0;
   }else{
     printf("We hit an error.\n");
     return 1;
   }
 }