Fixed compare editor when working with dirty files

[kittaakos]

Signed-off-by: Akos Kitta kittaakos@typefox.io

What it does

This PR fixes the content of the diff editor when working with dirty resources.

How to test

• Disable the auto-save,
• Create an empty file,
• Write foobar in the editor, do not save it.
• Open Search view, write bar to the search input and baz to the replace input.
• Double click on the tree item, so that the IDE opens a diff editor.
• Verify that the right-hand side editor shows foobaz. Without the fix, baz is in the right-hand side editor.

Please review.

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

[vince-fugnitto]

I confirmed that the changes fixed the bug as described 👍

[kittaakos]

Thank you so much for the review <3