Revert "Finish input when the screen state is off"

This reverts commit 0df88124.

The original CL is trying to reduce the dependency of PownerManager to
finish input when screen off by using display state.

However, it doesn't fully fix the original Bug 26851566 since we only
finish input connection but didn't callback onFinishInput callback for
IME client.

Also, for some scenarios, the window / view focus may not change
during screen turns off / on:
  - Focusing timing when disable keyguard, then quickly screen off / on.
  - Using P-sensor to turning screen off / on.

When the above scenario happens, makes input connection cannot re-start
and soft-keyboard can't be shown.
(The recovery is manually focus on next window or activity.)

As the above reason, we need to re-consider the lifecycle of
input connection, window / view focus when not only screen state but also
device inactive state when always-on-display.

Fix: 156045961
Fix: 154605805
Bug: 26851566
Bug: 156215187
Test: atest CtsInputMethodTestCases
Change-Id: If06daf71160aa44a4254ac125561974ecbdef4f2