[sql] Import reference version of SQLite 3.7.6.3.

third_party/sqlite/sqlite-src-3070603/src/btree.c

 /*
 ** 2004 April 6
 **
 ** 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 8123 matching lines @@
           aData[18] = (u8)iVersion;
           aData[19] = (u8)iVersion;
         }
       }
     }
   }
 
   pBt->doNotUseWAL = 0;
   return rc;
 }