Rework the logic that factors constant expressions out of inner loops, making
it both simpler and faster.

FossilOrigin-Name: 8dc5c76c766828d7c28090bec30ff48227e7b140
diff --git a/src/vdbeblob.c b/src/vdbeblob.c
index 0c4ebf6..a90c5b0 100644
--- a/src/vdbeblob.c
+++ b/src/vdbeblob.c
@@ -328,6 +328,7 @@
   }
   sqlite3Error(db, rc, (zErr ? "%s" : 0), zErr);
   sqlite3DbFree(db, zErr);
+  sqlite3ParserReset(pParse);
   sqlite3StackFree(db, pParse);
   rc = sqlite3ApiExit(db, rc);
   sqlite3_mutex_leave(db->mutex);