Move a call of queryInputMethodServicesInternal() to IO thread

With this CL

  InputMethodManagerService#queryInputMethodServicesInternal()

uopn

  InputMethodManagerService.Lifecycle#onUserUnlocking()

is now called on the IO thread.

Note that with this CL we also start calling it even when

  InputMethodManagerService#mSystemReady

is false, which is intentional and what we have started doing.

Basically users should not notice any change.

Bug: 343601565
Test: presubmit
Flag: EXEMPT refactor
Change-Id: I9799c764c3b404e42952b861b220c705445ed910