[Ayatana] Shadows around active window versus window tiling

[Ryan Prior <ryanprior@xxxxxxxxx>]

When the user tiles windows by dragging them to the left or right of
the viewport, they tile as to fit perfectly together. In order to
increase the impact of that illusion, I think it would be neat if the
window shadow for the active window would be supressed, so that one
shadow would not overlap the other. This puts the two windows on the
same "plane", rather than one in "front" of another.
Another tiny detail that could improve the illusion is to remove the
window corner rounding for the "seam" between the two tiled windows,
making them look more like one unit.

I can create a mock-up if that would be helpful to illustrate my idea.

Thanks,
Ryan