Bug 448361

SUMMARY
***
Dolphin is severely slowed down/halted/crashed by unavailable/slow/unstable network storage when these have been mounted with GIO/GVFS.
***


STEPS TO REPRODUCE
1. Mount an SMB share: `gio mount smb://user@share`
2. Disconnect the share server from the network/prevent access.
3. Try to open a new Dolphin session

OBSERVED RESULT

Dolphin may take more than 1 minute to open (even if it the directories it remembers and tries to open weren't dependent on the share) and subsequent navigation will be slow.

When running strace, I noticed this:

```
statx(AT_FDCWD, "/run/user/1000/gvfs/smb-share:port=445,server=127.0.0.1,share=e,user=shareuser", AT_STATX_SYNC_AS_STAT, STATX_ALL, 0x7ffee6161550) = -1 EIO (Erreur d'entrée/sortie) / (IO Error)
statx(AT_FDCWD, "/run/user/1000/gvfs/smb-share:port=445,server=127.0.0.1,share=e,user=shareuser", AT_STATX_SYNC_AS_STAT, STATX_ALL, 0x7ffee6161550) = -1 EIO (Erreur d'entrée/sortie) / (IO Error)
```

EXPECTED RESULT

Dolphin should only have a problem when trying to access files or folders on the faulty network mount and have a reasonable timeout when it tries to stat a directory that just won't open. Also, when while trying to access the problematic path, only the tab pointing on that path should be affected vs the entirety of Dolphin UI.

SOFTWARE/OS VERSIONS
Operating System: Arch Linux
KDE Plasma Version: 5.23.4
KDE Frameworks Version: 5.89.0
Qt Version: 5.15.2
Kernel Version: 5.15.11-zen1-1-zen (64-bit)
Graphics Platform: Wayland
Processors: 16 × AMD Ryzen 7 5800X 8-Core Processor
Memory: 62.7 Gio of RAM
Graphics Processor: AMD Radeon RX 6900 XT

ADDITIONAL INFORMATION

This was noticed with a SMB server from a Windows VM that was paused (the VM itself) while the share was still mounted. When resuming the VM, the share is responsive again (and so is Dolphin).