Followup task to T54653 to work on implementing the workflow changes proposed.
(Note: This is currently a lower priority item than fixing bugs to get 2.8 into a usable state for Spring team. But, I'll be working on this when I get time).
There are the following sub-tasks:
* ~~**Create operator for "Open Drivers Editor" functionality.**~~ rBc685c19df95
* ~~Basic opening functionality~~
* ~~Filtering support to get driven property under mouse at the time the "active" driver~~
* **Eyedropper support for clicking in 3D view and getting menu of common properties to drive, based on item under mouse.**
* Basic object support
* Investigate possibility of bone support too. (NOTE: Last time this was tried, it turned out being too complex to accomplish)
* Restore cursor feedback when eyedropper is active (T55147)
* **Clean up drivers editor ui** - rB57b47ebb284 (and followup commits)
* ~~Add more space for expressions box~~
* ~~Remove "Show Debug Info" checkbox - it's always needed~~
* ~~Remove "Update Dependencies" button by making it redundant~~ - Should be ok now without out. It's still in the UI, but will be removed soon
* Remove "Use Self"? Or rename?
* Add optional display of useful hints about syntax for expressions and/or what can be used
* **New persistent floating panel UI for adding and editing driver settings**
* Floating panel
* ~~Basic layout~~ - rB7e7680e33bb - Use a modified version of the existing drivers editing panel, and make it a popover
* Driver variable management (another eyedropper?)