Fix HINT_STATE not tracking the entire height of the screen

Explicitly use DeviceProfile#heightPx instead of getShiftRange(),
which might be less depending on AllAppsTransitionController

Test: swipe up from bottom on home, ensure workspace scales down
as the gesture goes all the way to the top of the screen

Change-Id: I9c2988d361c22d437c7eb9bea8ed715d06054c59