Focus shader text editor when opened with quick open dialog

[MartinDelille]

This is my first PR to the project so don't hesitate to ask me for improvements or any kind of modification.

I was a little bit annoyed that opening a shader with the Quick open dialog didn't focus it in the editor, so I added a line to focus the editor when opening a shader.

I'm not sure all the case are handled so feel free to comment on that.

[JekSun97]

I approve, this matches the behavior of the script editor.

[MartinDelille]

I wondered how I could make this changed merged. Shall I add it to the next call agenda ?

[paddy-exe]

@MartinDelille
First off congrats on your first PR!
Currently it's beta phase so there's a feature freeze. Your PR counts as a feature so it will have to wait until 4.4 stable is released.

[paddy-exe]

Tested and works as expected. Since this is a new feature, this will have to wait until 4.5.

Not sure if there are any style nitpicks applicable here.

[MartinDelille]

Thank you for the feedback @paddy-exe !

[kitbdev]

This PR currently only works for shaders that are already open (even if not switched to). If the shader hasn't been opened yet it won't get focused. It also doesn't work with ShaderIncludes.
Hovever, doing it for shaders that are closed (ideally in _switch_to_editor), would probably cause issues since it would take focus from the ScriptEditor when the editor is loaded. I'm not sure if that is easily solvable, so it's fine if we want to keep the current approach for now.

[MartinDelille]

I moved the focus grab to _switch_to_editor so it handles ShaderIncludes. The focus is indeed taken when the editor is loaded but I don't know how I can prevent that. Does it look acceptable now ?

[Chaosus]

Does it look acceptable now ?

You need to squash the commits, if it's ready - see https://contributing.godotengine.org/en/latest/organization/pull_requests/creating_pull_requests.html#modifying-a-pull-request

[MartinDelille]

Done: e761c71

[MartinDelille]

Has I said there is a little side effect: when reponing a project with opened shader, the shader editor will be focused. I think this is can be acceptable. If not I would appreciate a hint to optionally do the focus at startup. I think I would need to add the p_focus parameter to the edit() method but since it is an overriden method from the EditorPlugin class, it might have implication elsewhere.