Fix: line slop shouldn't always increase / decrease by one line
Touch slop is from the bottom (or top) of the line + line height / 2.
It only makes sense to apply touch slop if the user is within a line
from the previous line. Additionally, not doing this can cause some
undesirable behavior if the user moves very quickly and the selection
catches up with a weird line by line selection increase, potentially
even having the selection be stalled until a next move event.
This CL alters the logic so that if the user isn't within one line
of the previous selection, it'll just use whatever line the user is
1 file changed