Add @UserIdInt for InputMethodManagerInternal impls

This CL adds missing @UserIdInt annotations to
InputMethodManagerInternal implementation classes.

@UserIdInt is source-level annotation. There should be no impact on
change in build artifacts.

Bug: 192412909
Test: presubmit
Change-Id: I18067fd51eff6e9dece08b17f9ea1cf6ecedda68