Faster delete

On the web, I can quickly delete tens of messages by repeatedly hitting the delete button(which thankfully stays in the same place) very quickly. On Android you can only do like one per second because there's a delay. It may or may not just be an UI animation issue.

#301 might be a dependency of this to not fill up the screen with toast messages.

Start by reproducing rapid repeated message deletion on Android and trace the delete-button behavior, including the suspected UI animation delay. Check issue #301 for the toast-message dependency; done means users can delete successive messages at web-like speed without the current roughly one-second delay.

Written by the indexing model from the issue text.