fb: disable navigation bar camera button if widget carousel is enabled

Beside that the animation which starts when dragging the camera icon
to the left is broken if the user has enabled carousel animation like
tablets it does not feel natural even when we use the right animation for it.

So diable the camera button in this case and allow only swiping the camera widget on carousel mode

Change-Id: I6ba5eda7cd4603b1644ae088401b57861e4937a1