Don't set insets if task frame doesn't fit the screen

Set right and/or bottom insets to zero if the frame of the
task in multi-window mode doesn't fit the screen.
This covers the case when task has minimal width/height
which don't fit the visible area and task should be cropped.

Bug: 27621228
Change-Id: I741f1ef2e0994f7db0d49450fbb271e75f17a775