Fix camera launch delay from Keyguard

When we launch the camera from the lockscreen, we launch a
trampoline activity that launches a real activity. Now, under
certain race conditions the trampoline activity was resumed but
then set to invisible immediately again such that the window
was never relayouted. Thus, the activity was stuck in
WAITING_RELAYOUT state in UnknownAppVisibilityController, leading
to a app transition timeout.

To fix this, we immediately remove the app from the unknown
visibility controller as soon as it gets set to invisible again.

Test: Set animation scale multiplier to 0, open camera, finish
activity by pressing back, turn off screen, launch camera via
double tap, observe no delay.
Test: go/wm-smoke

Fixes: 37677242
Change-Id: I103a89af5fb515d6635f86abe2c67a02d90abd79