Remove hacky focus manipulation in DraftJS

[mirka]

I finally figured out what was causing the strange glitches that made me write some really hacky workarounds in #1193 and #1195. It was caused by focus events originating from NoteDetail, not NoteContentEditor! 💥

Testing

These things should work as expected:

• Checkboxes
• In the Note List, switching from a written note to an empty note (and vice versa)
• Place the cursor somewhere in the note text, and then create a new note
• Create a new note while the editor is not focused
• Remote changes coming in to the currently selected note

[roundhill]

So awesome! Nice job, it tested really well. Bye hacks 💥