Register remote transitions on activity start

Was only registering once, but launcher can stop/start
its activity (eg when changing gesture modes), so we
need to try and re-register every time

Bug: 200213691
Test: atest CloseAppHomeButtonTest
      change gesture mode and observe functional animations
Change-Id: I29f1eb647c2168d753e37f57657906979c5518be
5 files changed