Propagate userId to IMMS#finishSessionLocked()

With this CL

  InputMethodManagerService#finishSessionLocked()

can start getting the right userId through SessionState object.

There must be no observable behavior change in the single user mode.

Bug: 350386877
Test: presubmit
Flag: android.view.inputmethod.concurrent_input_methods
Change-Id: Id4f34e13877db43d4a4e6c3c01cc8e78001537df