Revert "Fix coding style violation"

This reverts commit 00e081a1ecc4b22b453c3aec863e86279cf16ff3.
Revert "Partitioning system: avoid leakage of resource"

This reverts commit f6bd30f2af5b97b4e133173150ab6e25d6f01bd1.
Don't delete session objects...

... disc->GetSession() doesn't allocate a new object, so delete
will cause problems later on.