Fix a couple minor but visible issues

- b/156431985 was not completely fixed -- when the PIP was below the
  shelf offset, opening the ime (ie. on the homescreen) would not
  push the PIP above the ime.  The logic to check if the PIP was
  incorrect and should only be checking in each direction if the
  current bounds is above or below the area to be offset from
- the fix for b/156431985 (ag/11453136) calls setAllowTouches to
  reset the touch state after the fling settles, but if the user
  touches and tries to grab the PIP while it is settling, the
  subsequent call to reset will prevent that new touch gesture
  from working.  Instead we can just reset the touch state
  on up after we calculated everything we need for the fling

Change-Id: I0b3265780035bf6c7d7b74bf05a5ed07564740c6
Bug: 159959599
Test: Move pip above the auto shift region, show ime then go home
      and ensure it never moves the PIP (also landscape)
Test: Move pip into the shelf region, show ime then go home and ensure
      it shifts to show the ime and then goes back (also landscape)
Test: Move pip above the auto shift region, show ime then
      move the PIP above the ime, go home and ensure it shifts the
      pip down (also landscape)
Test: Fling the pip from the bottom of the screen to the top and try
      to grab it just as it settles, ensure that this works