preferences: restore preference state

[vince-fugnitto]

What it does

Fixes: #7746

The following pull-request adds functionality in order to restore the preferences-view state when reloading the application.

The state includes:

• restoring the search term and consequently the result.
• restoring the currently selected workspace scope.
• restoring the editor location (through the firstVisibleChildID.

Master:

master.mov

Pull-Request:

pr-search.mov

How to test

Search Term

1. start the application, and open the preferences-view
2. enter a search term (ex: fontSize)
3. the view should perform a search
4. reload the application, the search term should persist and the results should be updated

Scope

1. start the application, and open the preferences-view
2. switch scopes (user, workspace, folder (multi-root))
3. reload the application, the scope should be preserved

Editor

1. start the application, and open the preferences-view
2. scroll the editor (ex: to scss/lint)
3. reload the application, the editor should be preserved at the last visible child

Review checklist

• as an author, I have thoroughly tested my changes and carefully followed the review guidelines

Reminder for reviewers

• as a reviewer, I agree to behave in accordance with the review guidelines

Signed-off-by: vince-fugnitto vincent.fugnitto@ericsson.com

[colin-grant-work]

Code LGTM, and the functionality is as described. Thanks for picking up the slack left by the first Preference Widget commit 🙏

[vince-fugnitto]

I'll merge the pull-request tomorrow if there are no objections.