[BUG] Navigation in "Shared by link" misbehaves

Actual behaviour

Navigating from the details screen of some text document inside "Shared by link" backwards after opening it, gets you to the "Files" section.

Expected behaviour

Navigating from the details screen of some text document inside "Shared by link" backwards after opening it, gets you to the "Shared by link" section (where we started the navigation).

Steps to reproduce

1. Share by public link a text document.
2. Go to "Shared by link" section.
3. Press on the document just shared.
4. Open it with an external app.
5. Go back to the ownCloud app.
6. Press the back arrow in the toolbar or the physical back button of the device.

Can this problem be reproduced with the official owncloud server?
(url: https://demo.owncloud.org, user: test, password: test)
Yes

Environment data

Android version: 9

Device model: Samsung Galaxy S9

Stock or customized system: No

ownCloud app version: 2.19

Reproduce the flow from the Shared by link section through the document details screen, opening the document externally and returning to the ownCloud app. Start by tracing the toolbar back arrow and physical back button handling after that return. Done means both back actions return to Shared by link rather than Files.