[sql] Rewrite sqlite patching "system".

third_party/sqlite/patches/0002-Fix-expr.c-linker-error.patch

+From 32a044166e9c02466660549983589bbec39f5752 Mon Sep 17 00:00:00 2001
+From: Mike Mammarella <mdm@chromium.org>
+Date: Thu, 24 Sep 2009 17:03:24 +0000
+Subject: [PATCH 02/23] Fix expr.c linker error.
+
+This can be seen when compiled with a sufficiently optimizing compiler.
+
+Original review URL: http://codereview.chromium.org/231010
+---
+ third_party/sqlite/src/src/expr.c | 4 +++-
+ 1 file changed, 3 insertions(+), 1 deletion(-)
+
+diff --git a/third_party/sqlite/src/src/expr.c b/third_party/sqlite/src/src/expr.c
+index c0e9ba6..2699ae1 100644
+--- a/third_party/sqlite/src/src/expr.c
++++ b/third_party/sqlite/src/src/expr.c
+@@ -781,7 +781,9 @@ static Expr *exprDup(sqlite3 *db, Expr *p, int flags, u8 **pzBuffer){
+       }else{
+         int nSize = exprStructSize(p);
+         memcpy(zAlloc, p, nSize);
+-        memset(&zAlloc[nSize], 0, EXPR_FULLSIZE-nSize);
++        if( EXPR_FULLSIZE>nSize ){
++          memset(&zAlloc[nSize], 0, EXPR_FULLSIZE-nSize);
++        }
+       }
+ 
+       /* Set the EP_Reduced, EP_TokenOnly, and EP_Static flags appropriately. */
+-- 
+2.2.1
+