Track usage of merge request file header buttons
Originally from the discussion in #31300 (comment 255205324)
We want to understand how often people use each of the file header buttons when viewing a merge request's changes. To answer questions such as “what is the percentage of visits to the 'Changes' tab of merge requests where people use the 'Edit file' button?”
- Copy file path
- Toggle comments for this file
- Edit file
- Show full file
- View file @ SHA
- Review app link
Perhaps we can implement FE event tracking for this: https://docs.gitlab.com/ee/development/event_tracking/frontend.html