Relax condition to hide unready IME with fixed rotation

This reduces flickering when opening app in a different
orientation with IME, and the layering target is not the
opening app due to a ALT_FOCUSABLE_IM floating window.

Also
- Make sure mLastConfigReportedToClient detect changes
  if the window (e.g. IME) is a config listener of process.
  So it can report to redraw.
- Reduce duplicated hidden operation.

Bug: 271352469
Test: DisplayContentTests#testApplyTopFixedRotationTransform
Change-Id: I6d24b0ee5294f0e7e145a4cf24e1b142dc8569d6