WL#15524 Patch #2 TLS-safe upgrade of mgm socket to transporter

Post push fix.

NdbSocket::copy method duplicated the mutex pointer, leaving two objects
referring to one mutex. Typically the source will destroy its mutex,
making it unusable for target object.

Fix by use the transfer method instead.

Change-Id: I199c04b870049498463903f6358f79a38649f543

Author: zmur

storage/ndb/include/util/NdbSocket.h

@@ -47,13 +47,9 @@ class NdbSocket {
   * NdbSockets should be copied using NdbSocket::transfer(), which
   * invalidates the original, and transfers ownership of its ssl and
   * mutex.
-  *
-  * NdbSocket::copy() should only be used when the original is going
-  * out of scope.
   */
   static void transfer(NdbSocket & newSocket, NdbSocket & original);
   static NdbSocket transfer(NdbSocket & original);
-  static NdbSocket copy(const NdbSocket &s) { return s; }
 
   void init_from_new(ndb_socket_t);
   void init_from_native(socket_t fd) { ndb_socket_init_from_native(s, fd); }

storage/ndb/src/common/transporter/TransporterRegistry.cpp

@@ -3860,7 +3860,7 @@ NdbSocket TransporterRegistry::connect_ndb_mgmd(NdbMgmHandle *h)
                          __FILE__, __LINE__);
     ndb_mgm_destroy_handle(h);
   }
-  DBUG_RETURN(NdbSocket::copy(socket));
+  DBUG_RETURN(NdbSocket::transfer(socket));
 }
 
 /**