Move more code to VE
- Move toolbar styling to VE
- Use VE to calculate hasChanged, instead of keep track in MF
- Make the overlay element the same as the target element
- Move the edit switching tool to VE
Depends on Ieb4e4eb3 in VE to allow configuration of target element.
Depends on I89351e40 in VE for styling.
Bug: T96186
Change-Id: I049e3882b0325c0875a25186cbb368f6c5ae9c66