ndb - bugfix: tinyblob + replace => mysqld crash (no bug#)

mysql-test/r/ndb_blob.result:
  do not delete unknown parts of tinyblob
mysql-test/t/ndb_blob.test:
  do not delete unknown parts of tinyblob
ndb/src/ndbapi/NdbBlob.cpp:
  do not delete unknown parts of tinyblob

mysql-test/r/ndb_blob.result

@@ -428,6 +428,13 @@ delete from t1;
 select * from t1;
 a	b
 commit;
+replace t1 set a=2, b='y';
+select * from t1;
+a	b
+2	y
+delete from t1;
+select * from t1;
+a	b
 drop table t1;
 set autocommit=0;
 create table t1 (

mysql-test/t/ndb_blob.test

@@ -338,7 +338,7 @@ select * from t1 order by a;
 drop table t1;
 drop database test2;
 
-# -- bug-5252 tinytext crashes plus no-commit result --
+# -- bug-5252 tinytext crashes + no-commit result + replace --
 
 set autocommit=0;
 create table t1 (
@@ -352,6 +352,10 @@ select * from t1;
 delete from t1;
 select * from t1;
 commit;
+replace t1 set a=2, b='y';
+select * from t1;
+delete from t1;
+select * from t1;
 drop table t1;
 
 # -- bug-5013 insert empty string to text --

ndb/src/ndbapi/NdbBlob.cpp

@@ -947,6 +947,8 @@ NdbBlob::deletePartsUnknown(Uint32 part)
 {
   DBUG_ENTER("NdbBlob::deletePartsUnknown");
   DBUG_PRINT("info", ("part=%u count=all", part));
+  if (thePartSize == 0) // tinyblob
+    DBUG_RETURN(0);
   static const unsigned maxbat = 256;
   static const unsigned minbat = 1;
   unsigned bat = minbat;