Add a new, experimental logging interface designed to aid in debugging of
deeply embedded projects that use SQLite.

FossilOrigin-Name: 103321e37ae46eacfad4e127d13477ad5dd02bab
diff --git a/src/sqliteInt.h b/src/sqliteInt.h
index ff90e03..a576dd6 100644
--- a/src/sqliteInt.h
+++ b/src/sqliteInt.h
@@ -2370,6 +2370,8 @@
   int isPCacheInit;                 /* True after malloc is initialized */
   sqlite3_mutex *pInitMutex;        /* Mutex used by sqlite3_initialize() */
   int nRefInitMutex;                /* Number of users of pInitMutex */
+  void (*xLog)(void*,int,const char*); /* Function for logging */
+  void *pLogArg;                       /* First argument to xLog() */
 };
 
 /*