Update sqlite to 3.7.3.

third_party/sqlite/sqlite-poison.patch

-Index: src/btree.c
-===================================================================
---- src/btree.c 2009-09-09 06:45:19.000000000 -0700
-+++ src/btree.c 2009-09-14 18:17:53.000000000 -0700
-@@ -24,6 +24,12 @@
+diff --git a/third_party/sqlite/src/src/btree.c b/third_party/sqlite/src/src/btree.c
+index f57f132..b5c3ba8 100644
+--- a/third_party/sqlite/src/src/btree.c
++++ b/third_party/sqlite/src/src/btree.c
+@@ -22,6 +22,12 @@
  static const char zMagicHeader[] = SQLITE_FILE_HEADER;
  
  /*
 +** The header string that appears at the beginning of a SQLite
 +** database which has been poisoned.
 +*/
 +static const char zPoisonHeader[] = "SQLite poison 3";
 +
 +/*
  ** Set this global variable to 1 to enable tracing using the TRACE
  ** macro.
  */
-@@ -2337,6 +2343,7 @@
-   if( rc ) return rc;
-   memcpy(data, zMagicHeader, sizeof(zMagicHeader));
-   assert( sizeof(zMagicHeader)==16 );
+@@ -2335,6 +2341,7 @@ static int lockBtree(BtShared *pBt){
+     ** in WAL mode. If the log is not already open, open it now. Then 
+     ** return SQLITE_OK and return without populating BtShared.pPage1.
+     ** The caller detects this and calls this function again. This is
 +  assert( sizeof(zMagicHeader)==sizeof(zPoisonHeader) );
-   put2byte(&data[16], pBt->pageSize);
-   data[18] = 1;
-   data[19] = 1;
-@@ -7804,4 +7811,72 @@
-   assert(!pCur->aOverflow);
-   pCur->isIncrblobHandle = 1;
+     ** required as the version of page 1 currently in the page1 buffer
+     ** may not be the latest version - there may be a newer one in the log
+     ** file.
+@@ -7949,6 +7956,74 @@ int sqlite3BtreeCheckpoint(Btree *p){
+   }
+   return rc;
  }
 +
 +/* Poison the db so that other clients error out as quickly as
 +** possible.
 +*/
 +int sqlite3Poison(sqlite3 *db){
 +  int rc;
 +  Btree *p;
 +  BtShared *pBt;
 +  unsigned char *pP1;
@@ skipping 50 matching lines @@
 +  /* Push it to the database file. */
 +  return sqlite3BtreeCommit(p);
 +
 + err:
 +  /* TODO(shess): What about errors, here? */
 +  sqlite3BtreeRollback(p);
 +  return rc;
 +}
 +
  #endif
+ 
+ /*