Fix potential memory leak in TClass::AdoptMemberStreamer #7426
Fix potential memory leak in TClass::AdoptMemberStreamer #7426

If dynamically-created member streamer cannot be add,
one have to delete it. Also it is good to issue error
olifre/root,root-mirror/root,root-mirror/root,root-mirror/root,root-mirror/root,root-mirror/root,olifre/root,olifre/root,root-mirror/root,root-mirror/root,olifre/root,root-mirror/root,root-mirror/root,olifre/root,olifre/root,olifre/root,olifre/root,root-mirror/root,root-mirror/root,olifre/root,olifre/root,olifre/root