Component is a simple `edit` button and a `more` menu for taking
per-file edit related actions, like reverting, renaming, and deleting
files.
Clicking any button will fire an event that will be caught and handled
by a higher-level component that has yet to be implemented.
Bug: Issue 4437
Change-Id: I1ded6d261562039b094ac2bafa60d7aa9603444b