Fixing generation of fake app-to-recents events

Due to some changes, Launcher started to generate these events also upon
pressing Home. Moving the generation to a right place triggered only
upon the app-to-recents transition.

Bug: 72967764
Test: atest google/perf/app-transition/app-transition-to-recents
Change-Id: I48e9450765474ed103e558b60ff5bf2b7d6b497d