Revert "Have WM use token info. from IMMS to determine IME target window"

This reverts commit daab865344fcfa45fe2789e43462f730a44fba64.

IMMS is currently sending wrong target candidates, so we need to revert
this until we figure-out what is going on there :(

Bug: 31559891
Bug: 35903813
Test: DisplayContentTests
Change-Id: I5c5beff4bac1b0781fa6663b13ff0dfe83a7806b
4 files changed