MessageConnections are not freed when NetworkDialog is open

[cadaver]

Due to MessageConnectionTreeItem having a shared ptr to MessageConnection, a connection is never freed even after it closes, when the NetworkDialog is open. In a network client usage, this means leaking connections when performing repeated connection and disconnection.

[Stinkfist0]

The connection leakage in Tundra seemed to disappear after this fix: Adminotech/tundra@1de67f3

[juj]

By leaking, do you mean actually leaking allocated raw memory pointers? Or leaking network memory sockets after MessageConnections are deleted? Do the MessageConnections properly clean up when all dialogs are closed, i.e. is it just a temporary held-alive reference by the NetworkDialog code, or are you actually seeing that connections stay unclosed indefinitely even after the user closes the dialog?