Add all apps education tutorial.

* Added FeatureFlag.ENABLE_ALL_APPS_EDU
* When user swipes up on nav bar three times and goes to hint state
  consecutively, we show the new All Apps education tutorial.
* For now we block interaction while the animation is playing,
  and we remove the view when the animation is done.
* Future CL will leave view up until user successfully reaches All Apps state.

Bug: 151768994
Change-Id: I903e0a3914d0558950ecb8cd714d97ddc10ca06b