Remove flag for keyguard remote animations [1/n]

Prepare for the removal.

Changed meaning of the parameters of handleStartTransitionForKeyguardLw()
They used to indicate if KEYGUARD_GOING_AWAY or (UN)OCCLUDE) transition
has just started. With this change, the arguments now specify if the
WindowManager immediately calls the old IKeyguardService API.

The argument "force" in PhoneWindowManager#setKeyguardOccludedLw() is
always false, so removed the argument.

Bug: 242833285
Test: Pass existing tests.
Change-Id: Ia849b393adfd2bd713ce31239f2e9207b9ad8716