
This reverts commit 085102be74f4c98094712a165e5128feaca50438. We need the SignalManager map top be iterable at shutdown for some of the following changes. A WeakMap is not iterable. This revert changes it back to a regular Map, which re-introduces the leaks caused by this. Those will be fixed differently by the two followup commits. Part-of: <https://gitlab.gnome.org/GNOME/gnome-shell/-/merge_requests/2466>