Rely on Display#getRealSize when dumping XML hierarchy

* Previously, the height returned by Display#getSize was used to
  determine visible objects. Based on the API level and the presence of
  system decorations (e.g. notches), this can cause objects near the
  bottom of the screen to be considered out of bounds (i.e. only objects
  within y=0 and y=partial_height are considered even if the omitted
  decorations are at the top of the screen).

Bug: 193270758
Bug: 188156320
Bug: 27537269
Test: manual
Change-Id: Iba21245c947cec0d0054f6d86e3585ba73233223