Revert "Some clean-up of divider code in preparation for bugfixes"

Revert submission 10602670

Reason for revert: Breaks WM pre-submit
Reverted Changes:
I68f1b47e0:Some clean-up of divider code in preparation for b...
Ifcac72f0f:Don't apply ime adjustments/dims if split is not a...

Bug: 150781668
Change-Id: I8a497b395f25865b476590c3c0cb98133b94ac8e