Fix waitingForDrawn callback not called when adjusting for IME

Test: Go into multi-window, with IME target at the top. Open IME,
lock screen and immediately unlock with fingerprint. Make sure
you don't end up with a unrecoverable black screen.

Change-Id: I1b9dd3aab64454e2d2894f5f273b70385615c74f
Fixes: 32544627