Improve collection edit performance

[keikari]

No description provided.

[tzarebczan]

Awesome, thank you! Saw the discussion in the issue as well.

[infinite-persistence]

Just a quick check, Miko:
the previous code performs the deletion for both QUEUE_EDIT and COLLECTION_EDIT, but now it's only for the latter. Does it need to happen for both? (not familiar with the purpose of these 2 lists).

[keikari]

Didn't thought about that, but should still be fine.

updated seems to be used to keep track of the last edited timestamp in cases where one decides to clear edits instead of publishing them.

unsavedChanges is used so that changing the sorting of the list won't become permanent until user saves the changes. It's only used in the "Arrange"-mode.