Fix IME hiding animation being delayed after unlocking the device

Hide keyboard with WindowInsetsController if could. In case
hideSoftInputFromWindow may ignored by input connection being finished
when the screen is off.

Bug: 233158645
Test: manual as steps:
  1.  Launch AllApps.
  2.  Tap search bar to invoke IME.
  3.  Screen off.
  4.  Screen on.
And all other keyboard hide cases such as back gesture, swipe down, etc.

Change-Id: I4154f38f94b6760a430f7510a650422020d8f59a