Bigbluebutton: Deleting current presentation should auto-select default.pdf

[ffdixon]

Describe the bug
When a user deletes the current presentation, the presentation area in BigBlueButton goes blank. It's not clear to the user they need to select another presentation after deleting the current presentation.

To Reproduce
Steps to reproduce the behavior:

1. Go to https://test.bigbluebutton.org/
2. Upload a new presentation
3. Delete it (and then click 'Confirm')

Expected behavior
Revert back to default presentation

Actual behavior
Presentation area goes blank

Screenshots

BBB version (optional):
2.2.19

[ravi-ct]

In a way, I like how it behaves in 2.2.19. An unintended consequence of this behaviour is that now we have a way to make all viewers go back to bigger webcam views due to the absence of the presentation as soon as the presentation is done with.

We were notified of this behaviour by one of our school customers who thanked us for automatically making the webcams bigger as soon as they delete their presentation. :wink:

[Jossef-767]

That's right, right now, it's the only way to control the enlargement of the webcams area.

[matiasilva]

@Jossef-767 you could just minimize the presentation, no? or have the presentation area hidden by default? In any case, the best way in my opinion is to have layout changes pushed to users and not to keep this (again imo) bug.

[daminebenq]

what we should have is that we should add an automatic selection of default presentation onClick on both of (trash-icon + modal confirmation button)