Revert "Immersive: Fix black bar in some games"

This reverts commit 73e32d9422c7790a8f9a95f93e224ea6f73ac79f.

Reason why: https://plus.google.com/102019442526033938148/posts/T2DgbKfwWHC

Sadly is due to apps' developers.
So if they don't add full immersive support just disable forced mode.
I may send a mail to them @kevdliu :)

Signed-off-by: Carlo Savignano <stevewatersy@gmail.com>
Conflicts:
	policy/src/com/android/internal/policy/impl/PhoneWindowManager.java