Dashboard live view: a tab that closes itself stays visible until another tab action runs

[kevingatera]

What happens

When the streamed page closes its own tab (for example via window.close()) or the tab crashes, the live view keeps showing the closed tab's last image and the tab bar still lists the closed tab. The view only recovers after another tab is opened or a tab command runs. Closing a tab through the CLI or the dashboard's close button works correctly.

Steps to reproduce

1. Start the dashboard and open a session with two tabs.
2. In the active tab, run window.close() (or let a page close its own tab).
3. The live view freezes on the closed tab's last frame and the tab bar still shows both tabs.
4. Open a new tab. The view and tab bar jump back to reality.

Expected

A tab that closes by itself disappears from the tab bar right away and the live view switches to a remaining tab.

Tested on Linux with the Chrome engine, current main (0.33.0).