Try to reload a notebook editor when its viewtype is installed or enabled

[bpasero]

Related to #179224

Enabling a notebook extension should ideally reload the editor with that view type without having to jump to another editor and back:

[rebornix]

In this scenario:

• Open NotebookEditorInput, it doesn't resolve and throw an error with actions
• Actions are rendered now in a Placeholder editor
• Serializer enabled, editor/view type provider registered

I'm not sure where is the best place to register the view type listener. IMHO we should register this in notebook land, but I'm a bit unclear of the lifecyles of the viewmodel/models:

• NotebookEditor is disposed after the error is thrown and it's replaced by the Placeholder Editor
• NotebookEditorInput is still alive (I guess?) but it's weird to have a listener inside it and trigger an editor reopen. Opening an editor from an editor input doesn't feel right

@bpasero any suggestion?

[bpasero]

@rebornix this flow seems to actually work fine when I use the button in the placeholder editor:

Given that, I am fine closing this as out of scope for now given it will not be the primary interaction from the user most likely.

I notice however, that when the extension is not installed, you briefly switch to the extension editor and then back to the notebook, I wonder if that flow can be made smoother.

[bpasero]

Hm, actually it may be nice to show the extension to the user so that the user gets to see what is being installed. Maybe we just leave it like this!

[rebornix]

@bpasero yeah that's the default experience of Install Recommended Extension. It gives users more awareness what's being installed.

Let's close this for now and see if we want to improve this later.