Send KEYCODE_SLEEP and KEYCODE_SOFT_SLEEP to status bar.

Wear SystemUI needs to react to KEYCODE_SLEEP and KEYCODE_SOFT_SLEEP
during TTW opt state in order to put the screen state back to OFF or
DOZE.

On wear, the device could be in sleep state while the screen is still
ON. During that state, we need to send sleep key code events (triggered
by palm gesture) to SystemUI so that SystemUI can turn off the display.

Bug: 293370294
Test: manual test
Change-Id: Ib96c4bfbcdffeeacffdd373d41d523cd5fd2be2d