Profile Picture deletion should have a confirmation dialogue

[anoadragon453]

Description

I just tried to exit settings and ended up hitting the other 'X' button, which cleared my profile picture. I type this as my old rooms are still having the profile picture be updated.

Steps to reproduce

• Go to Settings
• Go to close Settings
• Accidentally hit the small 'X', not the big 'X'
• cry

[turt2live]

Duplicate of #6656

[anoadragon453]

Ah, searching 'profile picture' didn't turn anything up, and neither did Github's new feature :P Thanks!