Update dismiss view location in one-handed mode

Updates dismiss view location in one-handed mode using margin instead of
padding. Dismiss view has internal padding that ensures it is not
against the bottom edge of the display. We were previously using padding
to update the dismiss view location in one-handed mode to ensure dismiss
view is visible. But when exiting one-handed mode, we cleared the
padding and dismiss view remained touching the bottom area of the display.
Switching to margin for repositioning dismiss view, when one-handed mode
is enabled. This ensures padding is not altered.

Update MagnetizedObject to use the same coordinate systems when
checking if a MagnetizedObject is in the bounds of a MagneticTarget.
MagnetizedObject relied on View#getLocationOnScreen() to determine the
location of itself and the location of MagneticTarget.
For dragging and determining if pointer location is in the bounds of a
MagneticTarget, it used MotionEvent#getRawX/Y().
These two work in different coordinate systems.
View#getLocationOnScreen() returns the location in screen coordinates.
MotionEvent works in display coordinates. Usually these match. But not
in the case of one-handed mode. When one-handed mode is enabled, we
translate the screen surface, to move it closer to the bottom edge.
View location in terms of screen coordinates does not change. But
MotionEvent is still working in display coordinates.
This led to an issue where based on screen coordinates a MagneticTarget
was in one location and when using those values to compare to
MotionEvent, they did not match.

Introduced a screenVerticalOffset option to MagneticTarget which allows
clients to define how much the screen is offset. That value is used
during checks if a MotionEvent pointer location falls into the
MagneticTarget bounds or not.

Bug: 311251698
Test: atest MagnetizedObjectTest
Test: manual, have a bubble and enter one-handed mode, drag the bubble
  and observer the dismiss view shows up at the same location on the
  display, drag bubble around the screen, observe bubble is stuck to
  dismiss view when hovering around it
Change-Id: Ie556d880ce9cc0e9bc8f3683e1cd6010142b9de4