Updates to sqlite3_finalize() documentation.

FossilOrigin-Name: 8c5994cf8e5ae0c1cb8f655ac83e52e668e75c86
diff --git a/src/vdbeapi.c b/src/vdbeapi.c
index 8ae7c52..96a19e0 100644
--- a/src/vdbeapi.c
+++ b/src/vdbeapi.c
@@ -65,6 +65,8 @@
 int sqlite3_finalize(sqlite3_stmt *pStmt){
   int rc;
   if( pStmt==0 ){
+    /* IMPLEMENTATION-OF: R-57228-12904 Invoking sqlite3_finalize() on a NULL
+    ** pointer is a harmless no-op. */
     rc = SQLITE_OK;
   }else{
     Vdbe *v = (Vdbe*)pStmt;