Fix the positioning of the "Toggle-discussion" button
The following discussion from gitlab-ce!28440 should be addressed:
- [ ] @dpalubin started a [discussion](https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/28440#note_173781411): (+3 comments)
> @pslaughter I like the idea of using flex box instead of using margins/padding to center content. However, with the way the hierarchy of elements are set up, applying the flex box here will also cause the Toggle-discussion button to shift when resolving discussions.
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> What is your opinion on this? I would prefer the button to remain in the same position in both cases. I liked the appearance of having the button on the top right regardless of the position of the text to the left, as in this image:
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> This was the way it was showing up for me through the gdk in this merge request. To achieve this same effect using a flex box, the toggle discussion button would have to be taken out of note-header-info and moved to a higher level element
issue